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Chloride is used as conservative tracers to estimate hydrological pathways. Field data on treatment of municipal solid waste (MSW) leachate show that Cl is reduced in aerobic treatment. Here laboratory experiments simulating MSW leachate treatment are conducted to see if electrical conductivity (EC) reduction can be duplicated in the laboratory, and to find probable chemical or physical factors explaining EC and chloride reduction. The experiments include three leachate, eight artificial, and three control samples. Mean reduction of EC in the respirometers was 17% for the leachate and 25% in the artificial samples. There was close to zero reduction in the controls. Mean reduction of chloride was 45% in the artificial samples and 9% in the controls. The oxygen consumption was lower in the leachate samples during aeration, probably due to inhibitory compounds. There was no reduction in EC after chemical coagulation with A1 and organic coagulants, 31% reduction in the aerobic system, and 46% in the anaerobic system. Total organic carbon significantly influenced the oxygen consumption. The reduction of chloride and EC depended on the acidity (pH) of the leachate. Centrifugation showed an effect on EC and chloride concentration. Based on these results it seems that the reduction of chloride in leachate treatment depends on the formation of organic precipitates. DOI: 10.1061/(ASCE)0733-9372(2007)133:6(659) CE Database subject headings: Conductivity; Chlorides; Leaching; Municipal wastes; Aerobic treatment.

A neutral 2-site chloride selective compound is developed based on a 1,3-alternate tetrasubstituted calix[4]arene providing a preorganized supramolecular scaffold. The resultant supramolecular cavity is among the first to combine urea functional groups bridged with single methylene spacers to pyrene moieties.

The synthesis and reactivity of the first ruthenium dithiocarbonate complex [Ru([kappa.sup.2]-[S.sub.2]C=O)(dppm)[sub.2]] (dppm = bis(diphenylphosphino)methane) are reported. It is readily accessible in one step from the reaction of cis-[Ru[Cl.sub.2](dppm)[sub.2]] with NaOH and C[S.sub.2], a transformation proposed to involve a Ru[S.sub.2]-COH intermediate.

The bond strength of chloride peroxide (CIOOCI) is studied by photoionization mass spectrometry. The experimental results are obtained from the fragmentation threshold yielding ClO(super +), which is observed at 11.52 plusminus 0.025 eV.

The kinetics of the reactions of chlorinated methyl radicals (CH2Cl, CHCl2, and CCl3) with NO2 are studied in direct measurements at temperatures between 220 and 360 K using a tubular flow reactor coupled to a photoionization mass spectrometer. The radicals are homogeneously generated at 193 or 248 nm by pulsed laser photolysis of appropriate precursors.

A mixture of the tungsten allylimido complexes Cl(sub 4)(RCN)W[NC(sub 3)H(sub 5)] was examined as a single-source precursor for growth of tungsten nitride (WN(sub x)) or carbonitride [WN(sub x)C(sub y)] thin films. The nitrogen content was found to support the significance of facile N-C bond cleavage in the film growth.

A study is conducted which demonstrates that the excited-state composition of Ph3P-Au-C equivalent to C-phen-containing Re(I) complex can be best described as an admixture of metal-to-ligand charge transfer and triplet intraligand states most likely in thermal equilibrium. Time-resolved infrared (TRIR) spectroscopy data were most definitive in demonstrating that the excited state can be best described as being composed of metal-to-ligand charge transfer and (super 3)IL states in thermal equilibrium.

The proton transfer in NH3--HCl by only one molecule of catalyst was studied by using the MP2 method with the large 6-311++G(2d,2p) basis set. The results showed that the proton transfer occurred from HCl to NH3 when catalyst molecule A not only as a proton donor strongly donated the proton to the Cl atom, but as an acceptor strongly accepted the proton from the NH3 molecule in the cyclic H-bond structure.

A one-dimensional chain of interconnected single-molecule magnets (SMMs) is obtained that consists of [Mn4(hmp)6](super 4+) units bridged by chloride ions. The magnetization hysteresis loops for the complex are similar to those for an SMM and show significant coercive field and steps at regular magnetic intervals.

The integration of voltammetry, surface-enhanced Raman spectroscopy (SERS) and density functional theory (DFT) has helped in disclosing the mechanistic origin of the electrocatalytic properties of silver cathodes during the reduction of benzyl chloride. The mechanism has bridged classical electroreduction mechanisms and oxidative additions similar to those occurring during organometallic homogeneous activation of organic halides by low-valent transition-metal complexes.

Nanocomposites of polyaniline with some rare earth chlorides like neodymium chloride, europium chloride, and dysprosium chloride are prepared by chemical oxidative polymerization of aniline and their morphological, structural, thermal, optical, magnetic and electrical properties are studied. Permittivity of the sample is dominated by the grain boundary behavior in low frequency and by the grain phase in the high frequency and a Maxwell-Wagner capacitor model is used for describing the frequency dependence of real part of impedance.

A chiral aryl-triazole foldamer with two azobenzene end groups was synthesized to define a folded binding pocket for chloride ions that unfolds with UV light to liberate the chloride. Control of chloride levels using light is demonstrated by switching the conductivity of an electrolyte solution up and down.

The re-examination of the controversial arenium-ion versus cation-radical mechanisms for Scholl reaction by using DDH/[H.sup.+] together with Fe[Cl.sub.3] as oxidants has shown that the reaction has proceeded via a cation-radical mechanism. The feasibility of the dicationic intermediate, formed by the loss of two electrons, is shown by its generation from a tetraphenylene derivative by using DDQ/[H.sup.+] as an oxidant.

The [S.sub.N]2 reaction of the trifluoromethanesulfonate and bis(trifluoromethanesulfonyl)imide salts of dimethyl-4-nitrophenylsulfonium with chloride ion has followed different pathway to when the same salts have reacted in molecular solvents.

Commercially available zinc dust in the presence of LiCl was used to generate polyfunctional zinc reagents. The method avoids the handling of air- and water-sensitive zinc reagents and could be applied for large-scale industrial applications.

Several ab initio calculations and molecular dynamics simulations are employed to study the potential energy surfaces of dissociation and elimination reactions of acetyl chloride. The analysis reveals that the excited acetyl chloride molecules can not undergo the carbon-chlorine cleavage in a short period.

he reactions between oxazole or 5-aryl oxazoles and i-PrMgCl have generated the corresponding 2-Gringnard reagents, which has reacted with Weinreb amides to provide exclusively 2-acyl oxazole products. The method is used for both 5-(hetero)-aryl-substituted oxazoles and unsubstituted oxazole and it is applicable to the highly challenging case of 5-(pyridine-2-yl)-2-acyl oxazoles.

The products of the Cl atom and OH radical initiated oxidation of C[F.sub.3]CH=C[H.sub.2] in 700 Torr of [N.sub.2]/[O.sub.2], diluent at 296 K was studied by using FTIR-smog chamber techniques. It is shown that the OH radical initiated oxidation of [C.sub.x][F.sub.2x+1]CH=C[H.sub.2] lead to the formation of [C.sub.x][F.sub.2x+1]CHO in a yield close to 100%.

The formation of cations from [(NP[Cl.sub.2]).sub.3], hexachloro-cyclo-triphosphazene, with protic, alkyl, and silylium electrophilic reagents is explored. The potent chloride-abstracting silyl reagents of the type [R.sub.3]Si(carborane) are unable to abstract chloride from [(NP[Cl.sub.2]).sub.3], even though the coordinatively unsaturated [N.sub.2][P.sub.2][Cl.sub.5.sup.+] cations are accepted as a reactive intermediate in the ring-opening polymerization of [(NP[Cl.sub.2]).sub.3].

The tetrachlorouranium(VI) complex is formed in [Bmim][[Tf.sub.2]N] and [Me[Bu.sub.3]N][[Tf.sub.]N] from a uranium(VI) solution in the presence of a stoichiometric quantity of chloride ions at room temperature. The electrochemical analysis has shown specific interactions of the ionic liquid cation with the uranium anionic species.

The electrochemistry of PCl3 and POCl3 is studied by cyclic voltammetry on gold microelectrode in the ionic liquid [C4mpyrr][N(Tf)2] (1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonly)imide). Results reveal that the diffusion of PCl3 is usually slow (3.1 x [10.sup.-12] [m.sup.2][s.sup.-1].

The potential energy surfaces of isomerization and dissociation reactions for acryloyl chloride (CH2CHCOCI) in the S0, T1, T2 and S1 states are mapped with density functional theory, CASSCF, MP2, and MR-CI calculations. The T1, T2, and S1 states are respectively characterized as (super 3)pipi*, (super 3)npi3*, and (super 1)npi* in nature on the basis of the CASSCF wave functions and their electronic population.

A study was conducted to determine the solubility of [Al.sub.2][O.sub.3] in chloride-fluoride melts of KCl-NaCl-NaF mixtures of 0.425:0.425:0.15, 0.38:0.38:0.24, and 0.35:0.35:0.30 compositions and trace the thermal dependence of the solubility of these compositions. [Al.sub.2][O.sub.3] is slightly soluble in the KCl-NaCl-NaF mixtures of 0.425:0.425:0.15 and 0.38:0.38:0.24 compositions in the 973-1123 K temperature range and some increase of the solubility with temperature is also observed.

The preparation and oxidation of one platinum(IV) analogue of the anticancer drug AMD473, cis-[PtCl2(NH3)(2-pic)], is described. The electrochemical studies have revealed that cis,trans,-cis-[PtCl2(OH)2(NH3)(2-pic)] is reduced more readily than its pyridine analogue cis,trans-cis-[PtCl2(OH)2(NH3)(pyridine)] consistent with the steric clash in the former complex destabilizing the platinum(IV) oxidation state.

The implications of the disorder of the Cl-atom position in (CuCl)LaNb2O7 is explored by considering possible ordered structures of CuCl4O2 octahedra in each CuClO2 layer, by identifying various spin exchange interactions of a CuClO2 layer and by estimating the relative strengths of these interactions in terms of spin dimer analysis. The analysis has suggested that the CuCl4O2 octahedra of each CuClO2 layer should be arranged such that the resulting spin lattice does not have uniform chains but ring clusters containing an even number if Cu atoms.

The compositional change of the pure amorphous solid water (ASW) films deposited on the LiCl film is analyzed by using time-of-flight secondary ion mass spectrometry (TOF-SIMS) in the temperature range 140-155 K. Two phases of deeply supercooled water that lead to the dilute and concentrated LiCl solutions are clearly identified, where the former is short-lived and merges into the latter and the latter is basically identical to normal liquid water as far as the solubility of LiCl is concerned.

The ability of a simple molecular model of an ionic liquid is analyzed to describe the behavior of some transport properties of 1-ethyl-3-methylimidazolium chloride ([emim]Cl) as a function of the temperature as well as their mutual relationships, through equilibrium molecular dynamics (MD) simulations. The simulations have reproduced the slope of the Walden plots obtained from experimental data of [emim]Cl, thereby confirming that temperature does not change appreciably the extent of ion pairing.

The axially substituted complex chloro indium(III) 2-tetrabromo-3-tetra-(3,5-tetra-butylphenytoxy)napthathalocyanine [Br4][([tBu2]PhO).sub.4]NclnC are synthesized. It is shown that the bromination of the napthalocyanine ring considerably improves the limiting properties of such a system when high intensity radiations are produced by nanosecond laser pulses at 532 nm.

Dynamics strokes' shift measurements using coumarin 153 as the fluorescence probe is carried out to explore the effect of added electrolyte, lithium chloride on solvation dynamics in the Triton-X-100(TX-100) micelle and thus to understand the changes in micellar Palisade layer, especially the entrapped water structures in the Palisade layer. Solvation dynamics in the TX-100 micellar layer shows faster solvation with salt concentration up to about 1.5 M.

Energy splittings resulting from anisotropy and exchange interactions in the dimer of single-molecule magnets [Mn4O3Cl4(O2CEt)2(py)3]2.8MeCN are determined for both an undeuterated and a partially deuterated sample using inelastic neutron scattering. The antiferromagnetic (AF) exchange coupling between the two Mn4 subunits strongly depends on their separation.

The coordination of the U(IV) and U(VI) ions as a function of the chloride concentration in aqueous solution is studied by U L(sub III)-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. The EXADS measurements reveal that both U(VI) and U(IV) form complexes with mixed aquo and chloro ligands.

The porphyrin protonation is systematically studied in the presence of different anions in an organic, aqueous system and it is found that different anions caused distinctive spectroscopic and electroscopic features. The protonated form of porphyrin system does not interact with the anions that induce the porphyrin protonation.

A study is conducted to examine the cracking of an all-trans n-alkane, via idealized Lewis acid and Bronsted acid catalysis using density functional theory. However, results of exploratory optimizations of various intermediates with Al2Cl7(super -) as the catalyst are presented to provide the first step for future modeling studies in the ionic liquid system.

The issues raised by Riikka L. Puurunen after comparing the model of atomic layer deposition (ALD) growth to her own model are addressed. The two differential equations, describing the deposition of HfO2 per cycle, and the creation rate of new OH groups per cycle are used in the ALD model, whereas Puurenen's model is geometry based and takes into account the concentration of nucleation sites.

The origin of substrate-inhibited atomic layer deposition (ALD) growth is analyzed with two recent models of ALD, model A of Puurunen and model B of Alam and Green. Riikka L. Puurunen gives her responses to M.A. Green and M.L. Green's discontent on the way she interpreted and used their model.

Physical and electrical characteristics of atomic-layer-deposited HfO2 deposited using hafnium tetrachloride (HfCl4) and tetrakis(ethylmthylaminohafnium) (TEMAHf) precursors are investigated. The oxidant used for the solid HfCl4 is water, while ozone (O3) is used to oxidize the liquid TEMAHf.

A study hydrothermally synthesized flowerlike cupped-end ZnO microrod bundles from precursor ZnCl(sub 2-)(N2H4)2 in sheet shape at 140 degrees Celsius for 12 h. Uniform ZnO nanorods were obtained, using the same precursor rod shape under the same conditions, indicating that the shape of the precursor played a very important role in the final morphology of the ZnO sample.

Observations made during the reduction of the Ru(Super II)Ru(Super II) complexes {(Mu-L)[RuCl(Cym)]2}(PF6)n (CYM = p-cymene) with bridging L = 2,2'-azobispyridine = abpy and n = 1, or L = 2,5-bis(1-phenyliminoethyl)pyrazine = bpip and n = 2 using areneruthenium(II) complex fragments as precursors is presented. The observation of the enormalE intervalence charge-transfer (IVCT) features in the near-infrared region illustrates that mixed-valent diruthenium compounds can occur in unconventional configurations.

A systematic study is conducted that employs a hierarchy of theoretical methods to explore the effect of refining the treatment of electron correlation in determining the geometry and electronic ground state of the species. A relationship among structure, electronic properties and reactivity is established.

Dy(super 3+) - and Tm(super 3+) - doped lanthanum chloride was prepared by RAP of sol-gel lanthanum hydroxide. It was found that the emission intensity of Dy(super 3+) (1330 nm) and Tm(super 3+) (1220 nm) logarithmically increased with RAP temperature.

The solubility of 1-dodecyl-3-methylimidazolium chloride [C12mim] [Cl] in alcohols was measured by a dynamic method from 270 K to the melting point of the ionic liquid or to the boiling point of the solvent. The solubility of [C12mim] [Cl] in primary alcohols decreases with an increase of the molecular weight of alcohol from C6 to C12.