4,7-diphenyl-1,10-phenantroline from heterocyclic diamines and alizarine yellow R from chromogenic reagents have been used for spectrophotometric determination of manganese in the form of heteroligand manganese comple...4,7-diphenyl-1,10-phenantroline from heterocyclic diamines and alizarine yellow R from chromogenic reagents have been used for spectrophotometric determination of manganese in the form of heteroligand manganese complex. The complex formation and extraction condition, physical-chemical and analytical characteristics of this complex have been established. 5.5 - 11.0 pH range is observed as complex formation pH range. Extraction and stability constants were accordingly found as Kext = 8.32 × 1014 and lgβK = 7.2 ± 0.1. Molar absorptivity is ε = (2.27± 0.08) × 104 l·g-1·cm-1. In the range of 0.5 - 23.0 μkg manganese (II) Beer’s law is obeyed. The extraction-photometric methods of manganese determination have been worked out. The strangers ions influence on determination of manganese (II) has been studied. To determine amount of manganese in eggplant the proposed method was applied successfully.展开更多
Emerging contaminants constitute a set of substances that are released into the environment for which regulations are currently not established for their environmental monitoring, being antimony one of them. A new met...Emerging contaminants constitute a set of substances that are released into the environment for which regulations are currently not established for their environmental monitoring, being antimony one of them. A new methodology for Sb(III) traces monitoring by solid surface fluorescence is proposed. The metal was complexed with alizarine (Az) as fluorosphore reagent in alcaline medium in presence of the bile salt sodium cholate. To isolate the analyte of matrix constituents, a preconcentration/separation strategy on filter paper was introduced prior to determination step. The solid surface fluorescence was measured λem = 450 nm and λexc = 363 nm using a solid sampler holder. Under optimal conditions, the limits of detection and quantification of proposed methodology were 0.08 and 0.24 μg·L-1, respectively, showing a linear range from 0.24 to 304.4 μg·L-1 with good sensitivity and adequate selectivity. It was applied to the Sb(III) traces determination present in drinking water and beverages samples packaged in polyethylene terephthalate (PET) bottles widely consumed in Argentina. The combination of a preconcentration step on common filter paper and the inherent sensitivity of photoluminescent methods have permitted to achieve sensitivity similar to atomic spectroscopies using a lower price instrument typical in control laboratories. Precision and accuracy were tested with excellent agreement. Results were truenessed by ETAAS with satisfactory concordance.展开更多
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co...The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.展开更多
文摘4,7-diphenyl-1,10-phenantroline from heterocyclic diamines and alizarine yellow R from chromogenic reagents have been used for spectrophotometric determination of manganese in the form of heteroligand manganese complex. The complex formation and extraction condition, physical-chemical and analytical characteristics of this complex have been established. 5.5 - 11.0 pH range is observed as complex formation pH range. Extraction and stability constants were accordingly found as Kext = 8.32 × 1014 and lgβK = 7.2 ± 0.1. Molar absorptivity is ε = (2.27± 0.08) × 104 l·g-1·cm-1. In the range of 0.5 - 23.0 μkg manganese (II) Beer’s law is obeyed. The extraction-photometric methods of manganese determination have been worked out. The strangers ions influence on determination of manganese (II) has been studied. To determine amount of manganese in eggplant the proposed method was applied successfully.
文摘Emerging contaminants constitute a set of substances that are released into the environment for which regulations are currently not established for their environmental monitoring, being antimony one of them. A new methodology for Sb(III) traces monitoring by solid surface fluorescence is proposed. The metal was complexed with alizarine (Az) as fluorosphore reagent in alcaline medium in presence of the bile salt sodium cholate. To isolate the analyte of matrix constituents, a preconcentration/separation strategy on filter paper was introduced prior to determination step. The solid surface fluorescence was measured λem = 450 nm and λexc = 363 nm using a solid sampler holder. Under optimal conditions, the limits of detection and quantification of proposed methodology were 0.08 and 0.24 μg·L-1, respectively, showing a linear range from 0.24 to 304.4 μg·L-1 with good sensitivity and adequate selectivity. It was applied to the Sb(III) traces determination present in drinking water and beverages samples packaged in polyethylene terephthalate (PET) bottles widely consumed in Argentina. The combination of a preconcentration step on common filter paper and the inherent sensitivity of photoluminescent methods have permitted to achieve sensitivity similar to atomic spectroscopies using a lower price instrument typical in control laboratories. Precision and accuracy were tested with excellent agreement. Results were truenessed by ETAAS with satisfactory concordance.
文摘The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.