VOLUME I Introduction The Incentive Physical-Chemical Properties Experimental Methods Quantitative Structure-Property Relationships (QSPRs) Mass Balance Models of Chemical Fate Data Sources and Presentation Illustrative QSPR Plots and Fate Calculations References Aliphatic and Cyclic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References Mononuclear Aromatic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References Polynuclear Aromatic Hydrocarbons (PAHs) and Related Aromatic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References VOLUME II * Halogenated Aliphatic Hydrocarbons Chlorobenzenes and Other Halogenated Mononuclear Aromatics Polychlorinated Biphenyls (PCBs) Chlorinated Dibenzop-dioxins Chlorinated Dibenzofurans VOLUME III * Ethers Alcohols Aldehydes and Ketones Carboxylic Acids Phenolic Compounds Esters VOLUME IV Nitrogen and Sulfur Compounds Lists of Chemicals and Data Compilations Summary Tables References Herbicides Lists of Chemicals and Data Compilations Summary Tables References Insecticides Lists of Chemicals and Data Compilations Summary Tables References Fungicides Lists of Chemicals and Data Compilations Summary Tables References APPENDICES List of Symbols and Abbreviations Alphabetical Index CAS Registry Index Molecular Formula Index * Each chapter contains lists of chemicals and data compilations, summary tables, QSPR plots, and references

Handbook of Physical-Chemical Properties and Environmental Fate for Organic Chemicals

Aromatic components of coal: relation of distribution pattern to rank

Multidimensional separation methodology provides a mechanism for a very substantial increase in the resolving power of chromatographic and related systems. After defining the conditions required for multidimensional separation and reviewing the origin of its high resolving power, a comparison is drawn between the two principal kinds of multidimensional systems, represented by continuous two-dimensional operation and coupled column assemblies. It is shown that their roles are complementary. The two-dimensional system gives a broad powerful overview of a sample while the coupled column system can be used flexibly to magnify and resolve selected regions of the sample space.

Concepts and comparisons in multidimensional separation

The attenuation of gamma radiation was utilized to measure changing residual trichloroethylene (TCE) saturation in an otherwise water-saturated porous medium as clean water was flushed through the medium. A front over which dissolution actively occurred was observed. Once developed, this front varied in length from ≈11 mm to ≈21 mm, lengthening as it moved through the porous medium. Gamma attenuation measurements and analyses of effluent water samples indicate that there was minimal if any transport of TCE as colloidal droplets. Even as trapped TCE ganglia decreased in size due to dissolution, there is no evidence that they became mobile and advected downgradient. An extraction of the porous medium at the completion of one experiment indicated that less than 0.002% of the original TCE mass remained, suggesting that minimal amounts of separate phase TCE remained trapped within the medium after flushing with 290 pore volumes. Mass transfer rate coefficients were computed and are shown to be a function of Darcy flux, TCE volumetric content, and distance into the region of residual TCE.

An experimental study of complete dissolution of a nonaqueous phase liquid in saturated porous media

Prediction of the fate of hydrophobic organic contaminants in soils is complicated by the competing processes of sorption and biodegradation. To test the hypothesis that sorbed naphthalene is unavailable to degradative microorganisms, we developed a simple kinetic method to examine the rates and extents of naphthalene degradation in soil-free and soil-containing systems in a comparison of two bacterial species. The method is predicated on the first-order dependence of the initial mineralization rate on the naphthalene concentration when the latter is below the Michaelis-Menten half-saturation constant (Km) for naphthalene for the organism under study. Rates and extents of mineralization were estimated by nonlinear regression analysis of data by using both a simple first-order model and a three-parameter, coupled degradation-desorption model described for the first time here. Bioavailability assays with two bacterial species (Pseudomonas putida ATCC 17484 and a gram-negative soil isolate, designated NP-Alk) gave dramatically different results. For NP-Alk, sorption limited both the rate and extent of naphthalene mineralization, in accordance with values predicted on the basis of the equilibrium aqueous-phase naphthalene concentrations. For strain 17484, both the rates and extents of naphthalene mineralization exceeded the predicted values and resulted in enhanced rates of naphthalene desorption from the soils. We conclude that there are important organism-specific properties which make generalizations regarding the bioavailability of sorbed substrates inappropriate.

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Differential bioavailability of soil-sorbed naphthalene to two bacterial species.

The dynamic coupled column liquid chromatographic (DCCLC) method for determining the solubility of polycyclic aromatic hydrocarbons (PAH) in water is described. The DCCLC technique is a very rapid, precise, and accurate method for determining the aqueous solubility behavior of sparingly soluble organic compounds. The agreement of PAH aqueous solubilities and calculated solubility parameters, such as ..delta..Hs, with values that have been previously reported in the literature helps to confirm the validity of this approach. In all cases replicate solubility measurements of the generated PAH solutions at constant temperature were better than +- 3 percent and in most cases better than +- 1%. The lack of an appropriate physical parameter for accurately extrapolating PAH solubilities further enhances the utility of DCCLC method.

David H. Freeman

Papers

Determination of the solubility behavior of some polycyclic aromatic hydrocarbons in water

Determination of the aqueous solubility of polynuclear aromatic hydrocarbons by a coupled column liquid chromatographic technique

Review: ultraselectivity through column switching and mode sequencing in liquid chromatography

Particle porosimetry by inverse gel permeation chromatography

Development and characterization of ion-exchange bead microstandards.