Five anions (chlorate, perchlorate, nitrate, nitrite, and sulfate) and two cations (ammonium and potassium) in explosive residues have been separated and determined by capillary zone electrophoresis (CZE) with indirect ultraviolet detection. The electrolyte buffer for the cation separation was 10 mmol/L pyridine (pH 4.5) -3 mmol/L 18-crown-6-ether. Ammonium and potassium ions were baseline separated in less than 2.6 min with the detection limits of 0.10 mg/L and 0.25 mg/L (S/N = 3), respectively. The electrolyte buffer for the anion separation consisted of 40 mmol/L boric acid-1.8 mmol/L potassium dichromate-2 mmol/L sodium tetraborate (pH 8.6), and tetramethyl ammonium hydroxide (TMAOH) was used as electroosmotic flow modifier. All five anions were well separated in less than 4.6 min with the detection limit range of 0.10 - 1.85 mg/L (S/N = 3). The method was successfully used in real sample investigations to confirm the type of explosives.

A method was developed for the separation of imazethapyr enantiomers using capillary electrophoresis and large volume injection. Optimized buffer conditions were found using 6% hydroxypropyl-b-cyclodextrin as the chiral selector at pH 11 with an injection time of 20 s (0.5 psi). The limits of detection (LOD, S/N = 3) were 0.22 and 0.23 mg L -1 for the two imazethapyr enantiomers (imazethapyr-I and imazethapyr-II) respectively. The relative standard deviation was less than 5%. This method was successfully used in the study of enantioselective degradation of this herbicide in field soil and the results suggested that imazethapyr-I degraded at a higher rate when compared with imazethapyr-II.

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Fe(-Cl) 2 (phen)] n (1) and [Fe(H 2 O) 3 (phen)SO 4 ] (2) have been synthesized and characterized by single crystal X-ray diffraction analysis, IR and UV spectra. Complex 1 crystallizes in monoclinic system with space group of C 2/c and 2 crystallizes in monoclinic system with space group of P 21/c. The structure of 1 shows that each Fe(II) coordinates with one phen and four chlorides forming a distorted octahedral environment, and [Fe(-Cl) 2 (phen)] as a repeating unit forms a one-dimensional chain. The structure of 2 shows that each Fe(II) coordinates with one SO 2À 4 , one 1,10-phen and three H 2 O molecules; the crystal architecture is stabilized by hydrogen bonds and -interactions.