PVC based membranes of disodium salt of porphyrin 3,7,12,17-tetramethyl-8, 13-divinyl 2,18-porphine dipropionic acid (I) as ionophore with sodium tetra phenyl borate (NaTPB) as anion excluder and dibutyl phthalate (DBP), dioctyl phthalate (DOP), dibutyl butyl phosphonate (DBBP), tris(2-ethyl hexyl)phosphate (TEP), tri-n-butylphosphate (TBP) and 1-chloronaphthalene (CN) as plasticizing solvent mediators were prepared and constructed for determination of Zn(II). The PVC based membrane of (I) with DBBP as plasticizer and having anion excluder, NaTPB in the ratio PVC: I: NaTPB: DBBP (150: 10: 2: 200) gave the best results in terms of working concentration range (1.3×10-5 -1.0 ×10 -1 M) with a Nernstian slope (30.0 mV/decade of activity). The useful pH range of the sensor is 3.0 -7.4, beyond which a drift in potential was observed. The response time of the sensor is 10s and the lifetime was about 2 months during which it could be used without any measurable divergence. It had good stability and reproducibility. The membrane worked satisfactorily in non-aqueous medium up to 40% (v/v) non-aqueous content. M, respectively. The electrode has been used as an indicator electrode to determine the end point in the potentiometric titration of Zn 2+ with EDTA.

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Polyvinyl chloride (PVC) membrane electrodes based on porphyrin 5,10,15,20-tetrakis(4methoxyphenyl)porphyrinatocobalt (TMOPP-Co) (I) incorporating sodium tetra phenyl borate (NaTPB) as anion excluder and dibutyl phthalate (DBP), dioctyl phthalate (DOP), dibutyl butyl phosphonate (DBBP), tri-n-butyl phosphate (TBP), and 1-chloronaphthalene (CN) as plasticizing solvent mediators were prepared and tested for selective detection of molybdate ions. The membrane having anion excluder, NaTPB and DBP as plasticizer (membrane no. 2) proved to be best in terms of working concentration range 5.0×10-5 -1.0×10 -1 M with a near -Nernstian slope of 32.0±1.0 mV/decade of activity over the pH range 5.4-10.5. The response time of this sensor is 18s with a lifetime of about 4 months. The sensor can be used in non-aqueous medium with no significant change in the value of slope or working concentration range for the estimation of MoO 4 2-in solutions having up to 25% (v/v) non-aqueous fraction.

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Samples of effluent and sludge collected from the metal plating industry were treated by electrodialysis (ED), coulometry, and photocatalysis. The effects of different ED parameters (such as flow rate, applied voltage and current) and the single pass and recirculation methods on the percentage reduction of ionic components of an effluent sample and the percentage concentration of metal ions in the sludge solution have been determined. A maximum of 4040% reduction in the composition of effluent sample and about 39-47% concentration of metal ions in sludge solution have been obtained. The recirculation method for the concentration of metal ions at a high flow rate of sludge solution seems to be better than the single pass method at low flow rates. Copper, which is a valuable component in sludge samples, has been recovered by constant potential electrolysis with a coulombic efficiency of 90-97% and has also been deposited to 57-76% on a colloidal suspension of TiOz particles using UV and natural sunlight. The effects of treatment of TiOz with Hz at 400°C and the nature of a sacrificial electron donor in contact to TiOz on the photodeposition of copper are discussed.

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Abstract:The requirement for computerization of detection of lung cancer disease arises ever since recent-techniques which involve manual-examination of the blood smear as the first step toward diagnosis. This is quite time-consuming, and their accurateness depends upon the ability of operator's. So, prevention of lung cancer is very essential. This paper has surveyed various techniques used by previous authors like ANN (Artificial Neural Network), image processing, LDA (Linear Dependent Analysis), SOM (Self Organizing Map) etc.