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Báo cáo vật lý: "SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF Pb(II) AND Cd(II) USING ARTIFICIAL NEURAL NETWORKS"

Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF Pb(II) AND Cd(II) USING ARTIFICIAL NEURAL NETWORKS | Journal of Physical Science Vol. 18 1 1-10 2007 1 SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF Pb II AND Cd II USING ARTIFICIAL NEURAL NETWORKS Azizul Isha1 Nor Azah Yusof1 Mazura Abdul Malik1 and Hazlina Hamdan2 department of Chemistry Faculty of Science 2Faculty of Computer Science and Information Technology Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia Corresponding author azah@fsas.upm.edu.my Abstract A method for simultaneous analysis of Pb II and Cd II has been developed by using artificial neural network ANN . This method is based on the difference concentration of Pb II and Cd II with 4- 2-pyridylazo -resorcinol PAR . A feed forward neural network using back-propagation BP algorithm has been employed in this study. The input layer consists of seven neurons six neurons of hidden layer and two output neurons was found appropriate for the simultaneous determination of Pb II and Cd II . The network was trained up to 20 epochs with 0.0001 learning rate. This reagent also provided good analytical performance with reproducibility characters of the method yield relative standard deviation RSD of 0.44 and 0.94 for Pb II and Cd II respectively. The limit of detection of the method for Pb II and Cd II was calculated to be 1.9 and 0.4 mg l respectively. Keywords Pb II Cd II simultaneous determination artificial neural networks spectrophotometry PAR 1. INTRODUCTION More recently the application of artificial intelligence or expert systems in analytical chemistry and chemical engineering has emerged rapidly. ANN is a computing system made up of a number of simple and highly interconnected processing elements which processes information by its dynamic state response to external inputs.1 Pb II and Cd II are metals that appear together in many real samples. Several techniques such as flame atomic absorption 2 voltammetric3 and spectrophotometric4 5 methods have been used for the determination of these ions in different samples. Among this uv-visible .