When chloride concentrations are 5 ppb and 10 ppb, the standard deviations of six analytical results are 0.003 and 0.002 (absorbance unit) respectively.

From the results in eleven times determination of 1 ml aliquot of 2 μg of nitrite, the method gives a mean absorbance value with a standard deviation of 1.14×10~(-3) absorbance unit and relative standard deviation of 0.22％. The method is satisfactory for analysing nitrite in waters.

The absorbance unit(ABSU) for ACS group and UA group were significantly greater than it for non-ACS group(P﹤0.01). While there were no siginificantly difference between MI group and UA group(P=0.175). And even adjusted the concentration ofalbumin, the results were similar.

When 100?μL of a test solution was injected, the calibration graph was linear up to 240?pg for nickel(II), and the detection limit defined as three times the standard deviation of the reagent blank was 0.8?pg at 0.001 absorbance unit full scale.

The mean sensitivity for the complex, KCrIII [Fe(CN)5OH] is 1.86μg/ml/0.015 absorbance unit with an accuracy of 0.5% at 3-ppm level.

RESULTS: The mean percentage of total time less than 0.14 for use of the bilirubin absorbance unit was 12.4% in group B and 64.0% in group A.

With detector sensitivity set at 0.005 Absorbance Unit Full Scale, samples as little as 50 μl are sufficient to carry out the determination.

The apparent molar absorptivities and Sandell's sensitivities (in l mol-1 cm-1 and ng cm-2 per 10-3 absorbance unit, respectively) are 2.8×103 and 118.2 using PMA as oxidizing agent and 2.16×103 and 153 using MPA for the same purpose.

This paper studies the method of determining trace chloride in high purity power station waters, in which lead phosphate is used as load body for coprecipirating concentrated chloride. After speed centrifugation, the precipitate is dissolved with iron (Ⅲ) nitrate perchloric acid and the mercury (Ⅱ) thiocyanate-methanol solution is added, and then spectrophotometric determination is undertaken. In this paper, the principles and analytical conditions of this method are provided. The sensitivity of this method...

This paper studies the method of determining trace chloride in high purity power station waters, in which lead phosphate is used as load body for coprecipirating concentrated chloride. After speed centrifugation, the precipitate is dissolved with iron (Ⅲ) nitrate perchloric acid and the mercury (Ⅱ) thiocyanate-methanol solution is added, and then spectrophotometric determination is undertaken. In this paper, the principles and analytical conditions of this method are provided. The sensitivity of this method is 0.0026 absorbance/ppb cl~-, the concentration of detection limit is 2 ppbcl~-. When chloride concentrations are 5 ppb and 10 ppb, the standard deviations of six analytical results are 0.003 and 0.002 (absorbance unit) respectively. The recoveries of determing demineralized water samples are 88-98%. The apparatus used in this method are simple and the analytical procedures are convenient. The experiments verify that this method is of practical significance for determining trace chloride in high-purity waters of power station.

A new sensitive method for the determination of trace gold was described.Phenosafranine reacts with bromaurate to form an association complex having an absorption maximum at 527 nm.The apparent ε value at 527 nm is 5.2×10~4 and the Sandell sensitivity is 3.8×10~(-3) μg/cm~2.The complex can be extracted into 10 ml of isoamylacetate within 1 min.Optimum conditions for the extraction were found to be 1.6N in sulfuric acid,0.015M in sodium bromide and 0.03% of phenosafranine. Beel′s law is obeyed for 0 to 20 μg...

A new sensitive method for the determination of trace gold was described.Phenosafranine reacts with bromaurate to form an association complex having an absorption maximum at 527 nm.The apparent ε value at 527 nm is 5.2×10~4 and the Sandell sensitivity is 3.8×10~(-3) μg/cm~2.The complex can be extracted into 10 ml of isoamylacetate within 1 min.Optimum conditions for the extraction were found to be 1.6N in sulfuric acid,0.015M in sodium bromide and 0.03% of phenosafranine. Beel′s law is obeyed for 0 to 20 μg of gold per 10 ml.The colour of the extract is stable for up to 4 hr at room tem erature.The constituent ratio of the complex (Au to phenosafranine) is 1:1.From the 24 results by 10 ml aliquot of 10 μg of gold,the method gives a mean absorbance value of 0.524 with a standard deviation of 4.4×10~(-3) absorbance unit and a coefficient variation of 0.84%.And it has been used trially in analysis of ores,anode mud and copper-base alloys.

Anew spectrophotometric method for the determinat ion of trace nit rite was described. The method is based on a reaction of nitrite with Safranine Tto form red colour complex with an absorption maximum at 600nm. The apparent ε value at 600 nm is 7.39×10~31.mol~(-1).cm~(-1) and Sandell sensitivity is 9.34×10~(-3) μg/cm~2.Beers law is obeyed for 0 to 3 μg/ml of nitrite. The colour is stable for up to 6 hours at room temperature. From the results in eleven times determination of 1 ml aliquot of 2 μg of nitrite,...

Anew spectrophotometric method for the determinat ion of trace nit rite was described. The method is based on a reaction of nitrite with Safranine Tto form red colour complex with an absorption maximum at 600nm. The apparent ε value at 600 nm is 7.39×10~31.mol~(-1).cm~(-1) and Sandell sensitivity is 9.34×10~(-3) μg/cm~2.Beers law is obeyed for 0 to 3 μg/ml of nitrite. The colour is stable for up to 6 hours at room temperature. From the results in eleven times determination of 1 ml aliquot of 2 μg of nitrite, the method gives a mean absorbance value with a standard deviation of 1.14×10~(-3) absorbance unit and relative standard deviation of 0.22％. The method is satisfactory for analysing nitrite in waters.