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p-Decylphenyl isocyanide, p-C10H21-C6H4-NC or C17H25N, and p-decylbenzonitrile, p-C10H21-C6H4-CN or C17H25N, are isomorphous. The molecules lie in mirror planes, with the Ca rings perpendicular to the mirror. The packing of both molecules includes an aliphatic region, with close to ideal packing of the C10H21 chains, and an aromatic region, with phenyl ring-CN interactions. In addition, the CN ends of the molecules are also involved in a CN…NC dipolar interaction. [ABSTRACT FROM AUTHOR]

The epimerization of trityloxymethyl butyrolactol has been investigated using dynamic chromatography and an approximation function introduced by Trapp and Schurig that is based on stochastic and theoretical plate models. The epimerization rate constants and Gibbs activation energies of epimerization are directly calculated from chromatographic peak parameters, i.e. retention times of the interconverting species, peak width at half height and the relative plateau height by using the approximation function. The relationships between peak shape and chromatographic conditions, such as flow-rate, temperature and pH are investigated. [Copyright &y& Elsevier]

The article presents a study on Csp2-Csp2 reductive elimination. It states that the concept of reductive elimination has been in used for over 40 years and is believed as an important step in coupling reactions specially within the catalytic cycle. The study suggests that the experiments conducted have demonstrated the facile nature of Csp2-Csp2 reductive elimination process.

Headspace solid-phase microextraction (HS-SPME) was used in combination with gas chromatography-mass spectrometry (GC-MS) for the analysis of polycyclic aromatic hydrocarbons (PAH) at part per billion levels in fish oil samples collected from menhaden fish. The method was initially developed using fish oil from capsules spiked with a standard PAH mixture. The final HS-SPME-GC-MS method presented a linear range from 3 to 1,500 ng/g, with precision for most analytes <10% relative standard deviation. The limits of detection varied from 1 to 7 ng/g depending on the analyte. Real sample analysis was done on menhaden fish oil extracted from fish collected off the coasts of New Jersey and Louisiana. Naphthalene, fluorene, fluoranthene, pyrene, anthracene were detected at low levels of 70-180 ng/g in the real samples. The concentrations of PAHs detected in the real samples were well below established levels of concern for PAHs in finfish.

Raw menhaden fish oil was developed for biomonitoring polycyclic aromatic hydrocarbons (PAHs) using fluorescence spectroscopy. Menhaden (Genus Brevoortia) were collected in 2010 and/or 2011 from Delaware Bay, New Jersey, USA; James River, Virginia, USA; Vermillion Bay, Louisiana, USA (VBLA); and Barataria Bay, Louisiana, USA (BBLA). Barataria Bay, Louisiana received heavy oiling from the Deepwater Horizon oil spill. Method development included determining optimal wavelengths for PAH detection, fish oil matrix interferences, and influence of solvent concentration on extraction. Results showed that some fish oils contained high molecular weight PAH-like compounds in addition to other fluorescent compounds such as albumin and vitamin A and vitamin E. None of these naturally occurring compounds interfered with detection of high molecular weight PAHs. However, data suggested that the lipid component of fish oil was altering fluorescence spectra by supporting the formation of PAH excimers. For example, the most intense excitation wavelength for hydroxypyrene shifted from Ex285/Em430 to Ex340/Em430. Comparison of Deepwater Horizon crude oil and fish oil spectra indicated that some fish oils contained crude oil-like PAHs. Using wavelengths of Ex360/Em430, fish oil concentrations were calculated as 3.92 μg/g, 0.61 μg/g, and 0.14 μg/g for a Delaware Bay sample, BBLA 2011, and VBLA 2011, respectively. Overall, these results supported using menhaden fish oil to track PAH exposures spatially and temporally., (© 2015 SETAC.)

Dissolution studies are critical tests for measuring the performance of a drug product. We have developed a novel technique using in situ ATR-IR spectroscopy to monitor dissolutions of pharmaceutical drug products. The accuracy of this technique is +/-3% relative to HPLC using salicylic acid calibrator tablets and acetaminophen OTC tablets. This novel approach also gives the research laboratory the capability of analyzing individual ingredients in multiple tablets; for example, individual components of salicylic acid and acetaminophen tablets are easily distinguished. In addition, the individual ingredients of a multi-component tablet containing acetylsalicylic acid and acetaminophen are readily distinguished. The ATR-IR system was found to have good sensitivity and can analyze samples as low as 0.03 mg/ml. With improved sensitivity, this is a promising method for monitoring dissolution of pharmaceutical tablets with an excellent in situ capability for distinguishing individual components., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

A simple, precise, accurate and validated, acetonitrile-free, reverse phase high performance liquid chromatography (HPLC) method is developed for the determination of melamine in dry and liquid infant formula. The separation is performed on a Kromasil C18 column (150 mm x 3.2 mm I.D., 5 microm particle size) at room temperature. The mobile phase (0.1% TFA/methanol 90:10) is pumped at a flow rate of 0.3 mL min(-1) with detection at 240 nm. Melamine elutes at 3.7 min. A linear response (r>0.999) is observed for samples ranging from 1.0 to 80 microg mL(-1). The method provides recoveries of 97.2-101.2% in the concentration range of 5-40 microg mL(-1), intra- and inter-day variation in <1.0% R.S.D. The limit of detection (LOD) and limit of quantification (LOQ) values are 0.1 microg mL(-1) and 0.2 microg mL(-1), respectively., (Copyright 2010 Elsevier B.V. All rights reserved.)

Rhodium and iridium catalysts containing trifluoromethyl-substituted indenyl ligands (Ind'MCod, Ind' = C9H7, (1-CF3)C9H6, (2-CF3)C9H6, (1,3-CF3)2C9H5) have been developed for the directed hydroboration of 4-(benzyloxy)cyclohexene to cis-3-(benzyloxy)cyclohexanol. Compared to unsubstituted complexes, trifluoromethyl substitution yields a 3-10% increase in selectivity which is attributed to the strong electron-withdrawing effect of the trifluoromethyl group. Rhodium complexes give selectivities of 74-84%, and iridium complexes give high levels of selectivity (93-98%).

Union College is a small liberal arts college in the northeast with a good reputation in science. It is also one of the oldest schools in the nation, having been founded in 1795. Langmuir and Steinmetz taught here as did Chandler, the founder of the American Chemical Society and Ellery, one of the longest tenured Secretaries of Sigma Xi. Arthur and Carter became U.S. Presidents. We claim a Nobel Prize winner, the inventor of transistors, the person who developed the methods for producing quartz crystals and fiber optics. The presidents of du Pont and Kodak attended Union College. We are referred to as the "Mother of Fraternities," and we had the first radio station on a college campus (although not through the airways). Still, until recently, our reputation has been less than admirable among radiation safety experts. This article highlights some of the experiences of a new RSO at this well-acknowledged institution.