@article {2674,
	title = {Competitive Adsorption of Toluene and n-Alkanes at Binary Solution/Silica Interfaces},
	journal = {Journal of Physical Chemistry C},
	volume = {113},
	number = {47},
	year = {2009},
	note = {ISI Document Delivery No.: 520FMTimes Cited: 2Cited Reference Count: 48Yang, Zheng Li, Qifeng Hua, Rui Gray, Murray R. Chou, Keng C.},
	month = {Nov},
	pages = {20355-20359},
	type = {Article},
	abstract = {The competitive adsorption of toluene and n-alkanes at binary solution/silica interfaces was studied at room temperature using IR-visible sum frequency generation vibrational spectroscopy. The Surface coverage of toluene for toluene-pentane, toluene-heptane, and toluene-tetradecane mixtures was measured over the complete mole fraction range from 0 to 1. The competitive adsorption process was reversible, and the toluene coverage only depended oil the bulk mole fraction, not on the history of the system. The estimated molar adsorption free energy of toluene is 3.4 +/- 0.3, 1.8 +/- 0.3, and 0.84 +/- 0.3 kJ/mol higher than pentane, heptane, and tetradecane, respectively. Overall, toluene competes favorably on silica, and the molar adsorption free energy of alkanes increases as the chain length increases. It is consistent with the observed SFG spectra, indicating that the alkanes lie flat on the silica surface.},
	keywords = {ACCELERATED SOLVENT-EXTRACTION, bitumen, CONFORMATION, FREQUENCY VIBRATIONAL SPECTROSCOPY, H STRETCHING MODES, LIQUID-CHROMATOGRAPHY, NORMAL-ALKYL CHAINS, ORIENTATION, SUM-FREQUENCY, SURFACE},
	isbn = {1932-7447},
	url = {<Go to ISI>://000271826100033},
	author = {Yang, Z. and Li, Q. F. and Hua, R. and Gray, M. R. and Chou, K. C.}
}
@article {420,
	title = {Sample extraction for arsenic speciation},
	journal = {Canadian Journal of Analytical Sciences and Spectroscopy},
	volume = {47},
	number = {4},
	year = {2002},
	note = {ISI Document Delivery No.: 641DMTimes Cited: 15Cited Reference Count: 47Joint Meetings of EnviroAnalysis 2002/48th International Conference on Analytical Sciences and SpectroscopyMAY 27-30, 2002TORONTO, CANADA},
	pages = {109-118},
	type = {Proceedings Paper},
	abstract = {The standard method used to determine arsenic species in solid samples is by using an extraction method that minimizes any operationally induced changes in chemical form. However, the use of such methods often results in less than complete extraction, with extraction efficiencies ranging from <1\% to 100\% for many types of samples. In this study the effect on extraction efficiency of the variables of total arsenic content, sample type and extraction method (methanol/water vs. simulated gastric conditions) were examined. The arsenic content in plant and deer mouse samples from Yellowknife, NT, as well as commercially available hijiki, an edible alga, and their extracts, was determined. Statistical analysis of the results revealed that extraction efficiencies are lower for both plants and mouse tissues that contain the highest levels of arsenic, and this trend persists in plants even when more exhaustive extraction methods (Le., Soxhlet extraction) are used. When the plant data was examined with respect to taxonomic groupings moss appeared to be extracted less efficiently than most other plants, and sedge and cattail appeared to be extracted most efficiently. An extraction method modeling human gastrointestinal conditions, gastric fluid extraction (GFE), was comparable to methanol/water extraction of plants with respect to amounts extracted and proportions of As(III) and As(V) present. However, methanol/water was used more efficiently to extract arsenic from wet hijiki than the GFE method. It is important to include information about extraction efficiency when discussing speciation of arsenic in a sample.},
	keywords = {ACCELERATED SOLVENT-EXTRACTION, arsenobetaine, BIOAVAILABILITY, CANADA, CERTIFIED-REFERENCE-MATERIALS, CONTAMINATED SOILS, ORGANISMS, PERFORMANCE LIQUID-CHROMATOGRAPHY, PLANTS, PLASMA-MASS SPECTROMETRY, TERRESTRIAL},
	isbn = {1205-6685},
	url = {<Go to ISI>://000180729200004},
	author = {Koch, I. and Hough, C. and Mousseau, S. and Mir, K. and Rutter, A. and Ollson, C. and Lee, E. and Andrewes, P. and Granhchino, S. and Cullen, B. and Reimer, K.}
}
