Use of anion exchange resin-loaded paper in the determination of trace mercury in water by neutron activation analysis

Abstract

2-methyl-8-quinolinolato groups are similar to those found in the oxovanadium complex and in the aluminum(III) complex (J).The equation of the least-squares plane, with respect to the crystallographic axes, through the 2-methyl-8-quinolinolato group defined by the atoms N(l), C(l), . . . C(11), 0(12) is: 0.215* + 0.677T -0.728Z = -4.162 (Plane 2) and through the 2-methyl-8-quinolinolato group defined by the atoms N(21), C(22), . . . C(31), 0(32)is:-0.495* + 0.030Y + 0.999Z = 6.242where *, Y, and Z are in Á. The distances from the atoms in each of these groups to their respective planes are given in Table VIII. The carbon atom of the methyl group, C(ll), shows the maximum deviation (0.063 A) from Plane 2, and a ring carbon atom, C( 24), shows the maximum deviation (0.028 Á) from Plane 3. The gallium atom which is not included in the calculation of the least-squares planes lies 0.099 Á above Plane 3 and 0.133 Á below Plane 2. Although the coordinated 2-methyl-8-quinolinolato groups are approximately planar, there is considerably more distortion in this structure than in the oxovanadium(IV) structure. A comparison of the dihedral angles between the two intramolecular planes of the 2-methyl-8-quinolinolato groups reveals an important difference in the two structures. In the oxovanadium(IV) complex, the dihedral angle is 44°1', whereas in the gallium complex it is 69°45'. The distance between the 2-methyl-8-quinolinolato planes that are related by the center of symmetry (V4, lU, V4), is 3.55 A. The 2-methyl-8quinolinolato planes which are packed in a direction almost perpendicular to the c-axis are 3.89 Á apart when related by a center of symmetry, and 3.99 Á apart when related by a twofold axis (Figure 7). Intermolecular contacts that are less than 3.5 Á are shown in Figure 8.

Speciation of mercury with cold vapor atomic absorption spectrometry by selective reduction

“…chelates have been investigated in adsorption and size-exclusion chromatographic systems from viewpoints of the effects of ligand, metal ion, stationary phase substance, and mobile phase solvent (5)(6)(7)(8)(9).…”

“…Organomercury is determined by difference. Organomercury is usually decomposed with various oxidative digestions (8)(9)(10)(11)(12)(13)(14)(15)(16) or by UV light (17)(18)(19)(20)(21). Total mercury can be determined with Sn(II) without prior organomercury decomposition if Cd2+ is added at sufficient levels (20,21).…”

Evaluation of lyophilization for the preconcentration of natural water samples prior to neutron activation analysis

“…Other workers have devised chemical methods for removal of specific elements from water. Selective anion exchange was used by Robertson (7) to determine Ag in sea water and by Becknell et al (8) to measure Hg in fresh water. Nagatsuka et al ( 9) used an initial iron hydroxide coprecipitation step for concentration of rare earths from natural waters.…”

Preconcentration of trace metals in environmental and biological samples by cation exchange resin filters for x-ray spectrometry

“…Analytes which can be deposited in a thin layer on suitable substrates can meet these requirements. Preconcentration has been accomplished through the use of ion-exchange resin-loaded filter papers (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), or by coprecipitation of the analyte elements with chelating agents followed by collection on membrane filters (13)(14)(15)(16). Campbell et al (1) first characterized ion-exchange resin-loaded filter papers for preconcentrating microgram quantities of cations and anions for X-ray fluorescence analysis.…”