Analytical chemistry
Rasoul Pourtaghavi Talemi; Sajjad Bakhtiari; Nabi Javadi; Morteza Vatanparast
Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 93-105
Abstract
In the present study, we investigate the potentiometric behavior of Cu2+ carbon paste electrodes based on two mercapto compounds 2-Ethylmino-5-Mercapto-1,3,4-Thiadiazole (EAMT) and 2-Acetylamino-5-mercapto-1,3,4-thiadiazole (AAMT) self-assembled on gold nano-paricle (GNP) as ionophore. Then, the results ...
Read More
In the present study, we investigate the potentiometric behavior of Cu2+ carbon paste electrodes based on two mercapto compounds 2-Ethylmino-5-Mercapto-1,3,4-Thiadiazole (EAMT) and 2-Acetylamino-5-mercapto-1,3,4-thiadiazole (AAMT) self-assembled on gold nano-paricle (GNP) as ionophore. Then, the results obtained from the modified electrodes are compared. The self-assembled ionophores exhibit a high selectivity for Copper ion (Cu2+), in which the sulfur and nitrogen atoms in their structure play a role as the effective coordination donor site for the Copper ion. Among these electrodes, the best performance was obtained with the sensor with a EAMT/graphite powder/paraffin oil weight ratio of 4.0/68/28 with 200 µL of GNP exhibits the working concentration range of 1.6×10−9 to 6.3×10−2 M and a Nernstian slope of 28.9±0.4 mVdecade−1 of copper (II) activity. The detection limit of electrode was 8.9(±0.2)×10−10 M and potential response was pH independent across the range of 2.8–6.3. The proposed electrode presented very good selectivity and sensitivity towards the Cu2+ ions over a wide variety of cations including alkali, alkaline earth, transition and heavy metal ions. Also the proposed electrode was successfully applied as an indicator electrode in the potentiometric titration of Cu (II) ions with EDTA and the potentiometric determination of copper ions in spiked water samples.
Analytical chemistry
Moayed Avazpour; Sabah Shiri; Fariba Seifipour; Heshmatollah Nourmoradi
Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 106-118
Abstract
ABSTRACT: Water quality of dam storage is highly affected by upstream environment and basin. Regarding other conducted studies, there exist various reasons such as some studies and general monitoring of dams which cause some main problems including salinity, chemical and microbial pollution eutrophication, ...
Read More
ABSTRACT: Water quality of dam storage is highly affected by upstream environment and basin. Regarding other conducted studies, there exist various reasons such as some studies and general monitoring of dams which cause some main problems including salinity, chemical and microbial pollution eutrophication, and sedimentation. Chame-Gardalan Storage Dam in Ilam Province is one of the storages which have many environmental issues because of discharge upstream rural wastewaters, animal excreta, agricultural drainage, and leachate. The aim of this study is to signify the quality of Ilam’s storage Dam and also to recognize the pollutant resources and to analyze the pollutants’ behavior at different times and sites in order to determine dam properties for agricultural and domestic usages. Regarding the importance of the topic, the present study (in the year 2012) is based on the collected information of water quality of the basin, recognition of pollutant resources and measurement of qualitative parameters such as Temperature, TDS, EC, BOD5, COD, nitrogen, phosphor, and pH in seven periods of time (from May to November). The results show that the total increase in the concentration of all variables along the basin are over double, in particular, Nitrat, Sulfat, BOD, and COD. After analyzing data with some water quality indexes, we analyzed water quality of the storage and some strategies were applied in order to control of effect decrease in the dam storage which, a management program was presented to improve water quality.
Analytical chemistry
Sabah Shiri; Moayd Avazpour; Ali Delpisheh; Maryam Loeimyd
Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 119-128
Abstract
ABSTRACTA novel floatation-spectrophotometric extraction method was developed for the recovery of tin (II) from aqueous samples prior to determination by UV spectrophotometric detection. The method is based on the formation of a complex between tin (II) and kalmagyte in pH=8. The complex is floated in ...
Read More
ABSTRACTA novel floatation-spectrophotometric extraction method was developed for the recovery of tin (II) from aqueous samples prior to determination by UV spectrophotometric detection. The method is based on the formation of a complex between tin (II) and kalmagyte in pH=8. The complex is floated in the interface of n-hexane and aqueous phases. After removing the aqueous phase, the floated particles are dissolved in methanol and the absorbance is measured at 637 nm. Different parameters of the floatation-spectrophotometric technique such as reagent concentration, pH, surfactant, standing time and interfering ions were studied and optimized to obtain the best extraction results with the minimum interference from other compounds. Under these conditions, the extraction of the target compound was almost complete (mean values of recovery was more than 92.6%) in a short time (6 min). The optimized method demonstrated good linearity (r2 > 0.9991) in the range of 4-350 ng/mL, sensitivity (limit of detection for tin (II), 1.7 ng/mL), accuracy (0.19–7.35%) and precision (3.66%, 4.21%). The applicability of the proposed method was demonstrated by extraction of tin(II) from different water samples.
)
)
 by ... ', 'data/icc/coversheet/611388334830.jpg'))