Phosphorus speciation in the surface sediment and river water from the Orontes (Asi) River, Turkey.

The paper presents the results of the distribution of phosphorus bioavailability (total, organic, and inorganic phosphorus) in surface sediment and river water from the Orontes (Asi) River (Samandag, Antakya, Turkey) in March 2008. Speciation of inorganic phosphorus was carried out using a method on sequential extractions, with each releasing four forms of inorganic phosphorus-loosely sorbed phosphorus, phosphorus bound to aluminum (P-AL), phosphorus bound to iron (P-Fe), and phosphorus bound to calcium (P-Ca). Total phosphorus concentrations are, on average, 3.

A sequential extraction to determine the distribution of phosphorus in the seawater and marine surface sediment.

The distribution of phosphorus species among environmental compartments (e.g., between water and sediment), significantly affects the bioavailability of these species to organisms.

Sorption behaviour of uranium(VI) with N,N-dibutyl-N'-benzoylthiourea Impregnated in Amberlite XAD-16.

The sorption of U(VI) by N, N-dibutyl, N'-benzoylthiourea (DBBT) impregnated resin has been studied. DBBT impregnated resin was prepared by direct adsorption of chelating ligand onto macroporous support, Amberlite XAD-16. The adsorption of DBBT on the macroporous support is shown by FTIR spectroscopy to be the result of only weak chelating ligand-support interactions.

Effect of structural modifications of diaza-18-crown-6 on the extractability and selectivity of univalent metal picrates.

The solvent extraction of univalent metal cations with N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16 diaza-2,3,11,12-dibenzocycloocta deca-2,11-diene (L(1)), N,N' didodecyl-1,4,10,13-tetraoxa-7,16-diaza-2,3-benzocylooctadeca-2 ene (L(2)) and N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16 diaza-2,3,11,12-dibenzocyclo octadeca-2,11-diene (L(3)) with picrate anion into dichloromethane has been studied at 25 degrees C by UV-visible spectroscopy. The extractability and selectivity of univalent metal picrates (Li(+), Na(+), Ag(+), PhCH(2)NH(3)(+), NH(4)(+)) was evaluated as a function of [ligand]/[metal cation]. L(2) showed the highest extractability and selectivity for Li(+) over the larger studied cations, and also exhibited the highest [Li(+)]/[NH(4)(+)] selectivity as L/M=1.

The solvent extraction of alkali metal picrates with 4,13-N,N'-dibenzyl-4,13-diaza-18-crown-6.

Extraction of alkali metal picrates with N,N'-dibenzyl-18-crown-6 was carried out, with dichloromethane as water-immiscible solvent, as a function [ligand]/[metal cation]. The extractability of metal picrates (Li(+), Na(+), K(+), Rb(+), Cs(+)) was evaluated as a function of [L]/[M(+)]. The extractability of complex cation-picrate ion pairs decreases in this sequence: Li(+)>Rb(+)>Cs(+)>K(+)>Na(+).

Transesterified sesame (Sesamum indicum L.) seed oil as a biodiesel fuel.

The sesame (Sesamum indicum L.) oil was extracted from the seeds of the sesame that grows in Diyarbakir, SE Anatolia of Turkey. Sesame seed oil was obtained in 58wt/wt%, by traditional solvent extraction.

Comparison of microwave digestion procedures for the determination of some elements in asphaltite ash using ICP-AES.

A microwave digestion procedure for asphaltite ash was developed in an attempt to facilitate routine analysis and obtain reproducible conditions or comparable results. The conditions of the most effective procedure for 0.1 g asphaltite ash samples are 1 ml of HNO3 + 3 ml of HCl + 1 ml of HF + 1 ml of deionized water as acid mixture and 15 min for digestion time.

Levels of trace and major elements in illicit heroin.

Ten elements, aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), lead (Pb), and zinc (Zn) were analyzed in 44 illicit heroin samples from Southeast Anatolia, Turkey. Illicit heroin samples were dissolved in nitric acid using microwave oven and were quantified by electrothermal atomic absorption spectrometry (Cd and Pb) and inductively coupled plasma-atomic emission spectrometry (Al, Ba, Ca, Cu, Fe, Mg, Mn, and Zn). The most abundant element was calcium, 4050 to 14,200 microg/g, which could be ascribed to the use of lime in the manufacturing process and/or as diluting agent.