The infrared (IR) spectra of ultraviolet (UV) and thermally processed, methanol-containing interstellar/ cometary ice analogs at temperatures from 12 to 300 K are presented. Infrared spectroscopy, IH and _3C nuclear magnetic resonance (NMR) spectroscopy, and gas chromatography-mass spectrometry indicate that CO (carbon monoxide), CO2 (carbon dioxide), CH4 (methane), HCO (the formyl radical), H2CO (formaldehyde), CH3CH2OH (ethanol), HC(=O)NH2 (formamide), CH3C(_O)NH 2 (acetamide), and R--C_-N (nitriles) are formed. In addition, the organic materials remaining after photolyzed ice analogs have been warmed to room temperature contain (in rough order of decreasing abundance),hexamethylenetetramine (HMT, C6HI2N4), (2) ethers, alcohols, and compounds related to polyoxymethylene {POM, (--CH20--),}, and (3) ketones {R--C(=O)--R'} and amides {H2NC(=O)--R}. Most of the carbon in these residues is thought to come from the methanol in the original ice. Deuterium and 13C isotopic labeling demonstrates that methanol is definitely the source of carbon in HMT. High concentrations of HMT in interstellar and cometary ices could have important astrophysical consequences.The ultraviolet photolysis of HMT frozen in H20 ice readily produces the "XCN" band observed in the spectra of protostellar objects and laboratory ices, as well as other nitriles. Thus, HMT may be a precursor of XCN and a source of CN in comets and the interstellar medium. Also, HMT is known to hydrolyze under acidic conditions to yield ammonia, formaldehyde, and amino acids. Thus, HMT may be a significant source of prebiogenic compounds on asteroidal parent bodies. A potential mechanism for the radiative formation of HMT in cosmic ices is outlined.

Successful completion of organic chemistry is a prerequisite for many graduate and professional programs in science, technology, engineering, and mathematics, yet the failure rate for this sequence of courses is notoriously high. To date, few studies have examined why some students succeed while others have difficulty in organic chemistry. This study examines factors related to student performance in organic chemistry courses. Results indicate that high-achieving students, as measured by course grades, score higher on measures of conceptual performance and problem-solving while seeking assistance and engaging in practice problems earlier in the semester than low-achieving students. Case studies illustrate how students engaging in such behaviors can overcome poor prior grades while those not engaging in such behaviors can perform poorly despite strong prior grades. Overall, study behaviors and conceptual understanding outweigh prior academic standing in predicting final course grades. These analyses suggest potential intervention targets for educators addressing students at risk for poor organic chemistry performance.

The New Traditions Consortium comprises faculty from two-year colleges, liberal arts colleges, comprehensive universities, and research universities who are united by the common goal of effecting paradigm shifts in the chemistry learning experience. The primary sites of New Traditions activity have been Madison Area Technical College, College of the Holy Cross, Franklin and Marshall College, San Jose State University, University of Illinois - Urbana-Champaign, and University of Wisconsin-Madison. Individuals from a number of other institutions have contributed. Our approach has been to identify mechanisms of pedagogical/instructional change, implement them at different types of institutions, and evaluate their effects on student learning.

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The preparation, reactivity patterns, and *H NMR and optical spectral properties of the sulfmyoglobin, SMb, complex formed from equine myoglobin reconstituted with deuteroheme are investigated to shed light on the structure of the prosthetic group. The characteristic NMR spectral properties in both paramagnetic and diamagnetic derivatives of the initially formed green SMb show it to contain an iron chlorin with molecular/electronic structure very similar to that obtained with native protohemin (Chatfield, M.