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The geometries and energetics of complexes Li(super +), Na(super +), K(super +), Be(super 2+), Mg(super 2+) and Ca(super 2+) metal cations are studied with different possible uric acid anions (urate). The basis set superposition error (BSSE) corrected interaction energy is computed for these complexes and the atoms-in-molecule (AIM) theory has revealed that aqueous solvation has significant effect on the relative stability of complexes obtained by the interaction of urate with Mg(super 2+) and Ca(super 2+) cations.

Theoretical investigations are performed to study the phenomena of ground and electronic excited state proton transfer in the isolated and monohydrated forms of guanine. The singlet electronic excitation of guanine may not facilitate the excited state proton transfer corresponding to the tautomerization of the keto and enol form.

The potential of using flue gas desulfurization by-products (FGD) for the reclamation of acid minespoil was assessed in Tuscarawas County of Ohio, USA. In Treatment 1, 280 Mg [ha.sup.-1] of FGD was incorporated into the graded spoil to a depth of 20 cm. In Treatment 2, 280 Mg [ha.sup.-1] of FGD and 112 Mg [ha.sup.-1] of yard waste compost were incorporated into the graded spoil (FGDC). In Treatment 3, 112 Mg [ha.sup.-1] of limestone was incorporated into the graded spoil and was covered with 20 cm of graded borrowed topsoil (BTS). Six cores and six bulk soil samples were obtained from each treatment for the 0- to 10-cm depth in summer 2002. From the 10- to 20-cm depth, only bulk soil samples were obtained. Bulk and core soil samples were also collected from an unreclaimed spoil (SP) and a nearby unmined soil (UMS). Among the three reclamation treatments, BTS showed better soil quality with higher soil organic C (28.5 Mg [ha.sup.-1]), water-stable aggregation (556 g [kg.sup.-1]), and mean weight diameter (3.2 mm) of aggregates than FGDC or FGD treatments. The FGDC had higher soil inorganic and organic C than FGD. However, saturated hydraulic conductivity ([K.sub.8]), cumulative infiltration (I), infiltration rates at 5 min ([i.sub.5]) and 2.5 h ([i.sub.c]), and soil pH were similar among three treatments. Among treatments and controls, soil bulk density ([[rho].sub.b]) was lower for FGD, FGDC, and UMS than BTS and SP; and water-stable aggregation and mean weight diameter of the aggregates was higher for UMS and BTS than FGDC, FGD, and SP for both depths. The I and [i.sub.c], were similar among UMS and treatments. Reclamation improved the soil quality with higher soil pH ([approximately equal to] 7) and inorganic and soil organic C than in the SP. With respect to FGD, the soil organic C in FGDC increased at the rate of 0.64 Mg [ha.sup.-1] [yr.sup.-1] for the 0- to 10-cm depth. Overall, BTS was the best reclamation treatment. However, if topsoil is unavailable or transport is expensive, FGDC can be used as an effective reclamation material.

A comprehensive theoretical study of the vertical singlet and triplet electronic transitions of 4-thiouracil was performed at the multiconfigurational self-consistent field (MCSCF) level of theory. The ground and excited state molecular electrostatic potentials and the Mulliken charge distributions in different states were investigated.

Reclamation of disturbed soils is done with the primary objective of restoring the land. Therefore, measurement of physical and chemical properties of reclaimed minesoils (RMS) is essential for understanding the process of soil restoration. This study was designed to assess soil quality of two reclaimed sites and two nearby undisturbed sites in Jackson and Vinton counties, Ohio. Three different rates of fertilizers applied annually to the RMS at Jackson and Vinton County sites from 1979-1994 were: no fertilizer (FL1), 112-25-46 kg NPK [ha.sup.-1] (FL2), and 224-50-92 kg NPK [ha.sup.-1] (FL3). Bulk and core samples were obtained for only 0- to 10-cm depth for undisturbed (unmined) soil (UMS) and for 0 to 10 and 10 to 20 cm for RMS. A comparison within UMS and RMS showed that water-stable aggregation and mean weight diameter of aggregates (MWDs) were significantly higher for UMS than RMS for both sites (P < 0.05). Apart from soil bulk density ([[rho].sub.b]) for Vinton, no significant differences were observed in [[rho].sub.b], electrical conductivity (EC), pH, saturated hydraulic conductivity and water infiltration for the 0- to 10-cm depth among fertility treatments in RMS and UMS for both Jackson and Vinton County sites. Average soil organic C (SOC) 5 yr after reclamation in 1981 was 14.2 Mg [ha.sup.-1] for Jackson and 15.1 Mg [ha.sup.-1] for Vintun site for the 0- to 10-cm depth. In 2001, average SOC was 28.7 Mg [ha.sup.-1] for Jackson and 30.24 Mg [ha.sup.-1] for Vinton site. A two-fold increase in SOC was obtained at both sites between 1981 and 2001. Soil pH was >6.4 and was favorable for root development and biomass production at both reclaimed sites. No significant differences in several soil properties between UMS and RMS showed that fertility treatments improved the soil quality of RMS.

A systematic analysis of the effect of displacement length, soil texture, and steady state water flux (q) on solute transport was performed on saturated repacked loam and sandy loam soil columns to identify the simplest possible description that was consistent with the observations across all of the breakthrough curves (BTCs) for each data set. All 39 BTCs obtained from loam and 21 from sandy loam soils, with column lengths of 10, 20, and 30 cm, and a two-order magnitude variation in measured pore water velocity ([v.sub.m]), were fitted simultaneously and global estimates of parameters [dispersivity ([lambda]) and molecular diffusion coefficient ([D.sub.0])] were obtained. We showed that a two-parameter global dispersion relationship (D = [lambda][v.sub.m] + [D.sub.0], where D is the apparent diffusion coefficient) accurately represents the spreading process for all 39 loam soil BTCs ([r.sup.2] > 0.99), whereas a single global parameter (D = [lambda][v.sub.m]) was all that was required for the sandy soil ([r.sup.2] > 0.98). The globally fitted [lambda] was independent of displacement length and [v.sub.m]. D remained independent of [v.sub.m] in the lower velocity ranges; however, a linear relationship between [V.sub.m] and fitted D was obtained for [v.sub.m] > 0.1 cm [h.sup.-1] The results of this study illustrated the importance of molecular diffusion. In addition, we identified a nonlinear relationship between [v.sub.m] and average solute velocity ([v.sub.s]), which suggested that the anion exclusion volume decreased with increasing [v.sub.m].

Several miscible displacement experiments were carried out in three 10-, 20-, and 30-cm mollisol and antisol filled soil columns. A strong linear relationship between pore-water velocity (v) and apparent diffusion coefficient (D) was obtained for both soil columns ([r.sup.2] > 0.92). We also derived the nondimensional laws for equilibrium adsorption convective-dispersion equation (CDE) using inspectional analysis, which reduced the physical constants and variables in CDE from seven to four nondimensional-[pi] quantities. After scaling, the times of effluent arrival were nearly the same and all the breakthrough curves (BTCs) coalesced into a very narrow region of scaled time.