we found that dibenzo-18-crown-6 (db18c6) can be used as an ionophore to make a tin (ii)-ionselectivemembrane electrode. the electrode exhibits a near nernstian response for sn2+ ions over aconcentration range from 1.0× 10-6 – 1.0× 10-2 m with a slope of 27.5 ± 0.6 mv per concentration decadein an acidic solution (ph=1). the limit of detection was 8.0× 10-7 m. it has a response time of < 20s an...

a mixture of manganese, cobalt and lead para-amino benzoates supported on silica gel is used to catalyze oxidation of xylenes to toluic acids in presence of oxygen or air. reactions are clean and catalysts can be recovered easily and reused.

a pvc membrane ni(ii) ion selective electrode has been constructed using (1e,2e)-bis(2-aminophenyl)n&apos;1,n&apos;2-dihydroxyethanebis as membrane carrier. the electrode exhibited a goodpotentiometric response for ni(ii) over a wide concentration range 1.0×10-4 to 1.0×10-1m with aslope of 29.4±0.5 mv/decade a and a working ph range of 6.5-9.0. it had a fast response time of≤20s. the best perfo...

in order to study the cu(ii) ion selective electrode, an optimized membrane was prepared by mixing of 30 mg of pvc powdered, 5 mg of considered ionophore, 60 mg of plasticizer and 5 mg of additive. the sensor showed a near nernstian response for cu(ii) ions over a concentration range from 1.0×0-6 –1.0×0-2 m with a slope of 28.90.5 mv per concentration decade with a working ph range of 3.5-6.3. ...

selective harmonic elimination (she) is a powerful modulation scheme aims to find the required switching angles in order to eliminate the number of undesired harmonics. she is a complicated problem which consists of several nonlinear equations which have multiple local minima. in order to eliminate the higher number of undesired harmonics and as a result reducing the total harmonic distortion (...

a new polyvinyl choloride (pvc) membrane sensor for cerium (iii) was prepared based on 4,13-didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22dd) as an ionophore. the sensor exhibites a linear concentration range of 1.0×10-6to 1.0×10-1m, with a nernstian slope of 18.0±1.0 mv/decade, and a detection limit of 9.7×10-7m. it has a fast response time (5 s) and can be used for two mont...

schizophrenia is a debilitating and pervasive mental illness with devastating effects on many aspects of psychological, cognitive and social wellbeing. epidemiological and life-cycle data point to significant differences in the incidence and course of schizophrenia between men and women, suggesting that estrogen plays a “protective” role . adjunctive estrogen therapy has been shown to be effect...

the aim of this research was to determine the effect of selective exercise training on reducing the symptom of hypotonia and changing body composition in down syndrome adults. the research was performed in nemoneh disability rehabilitation centre of tehran. 24 men with down syndrome (mean age 26.185± 3.933) were randomly assigned to either a control (n=11) or an experimental group (n=13). the e...