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ORGANIC chemistry and PETROLEUM

ORGANIC chemistry and PETROLEUM

CHEMISTRY education in universities & colleges and ORGANIC chemistry

Discusses a modern approach to teaching organic chemistry. Organic chemistry courses must begin with structure. Suggests using nuclear magnetic resonance spectroscopy to introduce structure; Introduce students to symmetry axes and planes; Review valence of hydrogen and first-row elements; Give them the equation for calculating the number of sites of unsaturation from the molecular formula; Give students the results of 13C{1H} DEPT with details later; More.

POLYMER research and MASS spectrometry

Examines proposed partial least squares (PLS) multivariate statistical models for predicting concentration of hydrocarbon- and oxygen-containing functional groups for a calibration set of model homopolymers. Plasma-deposited films; Static secondary ion mass spectrometry (SIMS); PLS modeling; Preprocessing; Prediction of surface oxygen and hydrogen concentration.

NUTRITION education, HIGHER education, ACADEMIC degrees, UNIVERSITY & college entrance requirements, and COLLEGE teachers

The article provides information on the degree programs related to food science and human nutrition being offered by Colorado State University, Fort Collins. Peter J. Bechtel is the program director at the university. Entrance requirements include GPA with an aggregate of more than or equal to 3; courses in general chemistry, organic chemistry, biochemistry and physiology all with laboratories; and GRE aptitude test. The university offers both M.S. and Ph.D. degree programs. The M.S. program emphasis in nutritional science or applied nutrition is offered with either a thesis or non-thesis option. The Ph.D. degree emphasizes basic sciences with research in nutritional biochemistry, nutrition education or food science. The M.S. degree requires 35 credits and a final exam, whereas the Ph.D. requires a minimum of 50 credits beyond the M.S. Tuition and fees per year are $2,874.08 for resident and $8,572.08 for nonresidents. The faculty include K.G.D. Allen, J.E. Anderson, G.W. Auld, P.J. Bechtel, S. Gregary and others.

SEDIMENTATION & deposition research, OCEAN bottom, and CARBONATE minerals

Discusses the mechanism underlying the relative deposition rates of organic carbon and calcite to the sea floor. Effect of total calcite concentration on the specific depth at which calcite dissolves; Control of atmospheric carbon dioxide by ocean carbonate chemistry; Organic carbon degradation in the sediments.

GUMS & resins, ALLERGIES, COLOPHONS, GLYCERYL ethers, PATIENTS, and NUCLEAR magnetic resonance

In the esterification of rosin with glycerol, the main compound formed, glyceryl triabietate, shows low allergenic activity. In this study, compounds formed in smaller amounts, when abietic add (main component in rosin) was esterified with glycerol, were identified as glyceryl-1-monoabietate (GMA), glyceryl-1,2-diabietate (GDA,1,2) and glycery-1,3-diabietate (GDA1,3), using nuclear magnetic resonance (NMR), infra-red (IR) and mass spectrometry (MS) analyses. According to animal experiments, OMA was a contact allergen. No cross-reactivity was seen to allergens in unmodified rosin. Some patients allergic to unmodified rosin reacted when tested with GMA. No reactions were seen to the 2 diabietates. Some patients also reacted to commercial glycerol-modified rosins. OMA together with unmodified abietic acid were identified in these rosin samples. The reactions seen in rosin-sensitive patients to commercial glycerol-esterified rosins probably derive from the unmodified material still present in the product, but could also be the result of OMA obtained from the glycerol derivatization. [ABSTRACT FROM AUTHOR]

RING formation (Chemistry) and TRANSITION metals

Reviews the theoretical and mechanical metal-assisted cycloaddition transition reactions in organic chemistry. Organic and organometallic reactions; Schematically simulated reactions; Metal-assisted transition.

INSECT sex attractants, GRACILLARIIDAE, TORTRICIDAE, YPONOMEUTIDAE, OECOPHORIDAE, PYRALIDAE, GELECHIIDAE, and ALCOHOLS (Chemical class)

Field screening tests of 21 saturated and monounsaturated straight chain C12 and C14 alcohols and their acetates as well as some binary mixtures in dosages of 1 and 0.2 mg/dispenser were carried out in Lithuanian in 1993 and 1994. New sex attractants were determined for males of five moth species of the family Gracillariidae ( E10-12:OH for Phyllonorycter sorbi, E10-12Ac for Ph. cydoniella and Ph. oxyacanthae, Z10-12:OAc for Ph. junoniella, and a mixture of Z10-14:OAc with E9-14:OAc in a 1:10 for Ph. sylvella), for four species of the family Tortricidae ( E10-14:OAc for Endothenia ericetana, Z10-14:OAc in a 10:1 mixture with E11-14:OAc for Eudemis pozphyrana, E11-14:OAc in a 10:1 mixture with E11-14:OH for Dichrorampha petiverella and Cochylis dubitana), for two species of Gelechiidae ( Z9-14:OAc in a mixture with either Z10-14:OAc in a ratio 1:1, E9-14:OAc in a ratio 1:10 or E10-14:OAc in a ratio 10:1 for Bryotropha galhanella, Z10-14:OAc and E9-14:OAc in a ratio 10:1 for B. mundella), as well as for one species of each of the families Yponomeutidae ( Z7-14:OAc for Paraswammerdamia lutarea) and Oecophoridae ( Z10-14:OAc and E9-14:OAc in a ratio 10:1 for Pseudatemelia josephinae). Preliminary composition of sex attractants was established for three moth species of the family Gracillariidae ( Z10-14:OAc in a 1:10 mixture with E9-14:OAc for Phyllonorycter heegerella, Ph. coryli and Ph. dubitella) and for one species of the family Gelechiidae ( Z9-14:OAc for Bryotropha terella). Inhibitors of the sex attractants were found for four leafminer species of the family Gracillariidae ( Z7-, Z9- and Z10-12:OAc for Phyllonorycter sorbi, Z10-, E10-12:OH and E10-14:OH for Ph. mespilella, E10-12:OH for Ph. cydoniella, Z10-12:OH and E10-14:OH for Ph. oxyacanthae), for three species of Tortricidae ( E9-, Z11- and E11-14:OAc for Endothenia ericetana, E11-14:OAc for Gypsonoma minutana, E10- and E11-14:OAc for Epagoge grotiana), and for one species from the family Pyralidae ( Z10-, E10- and E11-14:OAc for Pyrausta aurata). Data from male behaviour tests in tube olfactometers are presented for Phyllonorycter blancardella, Ph. sorbi, Ph. dubitella and Ph. strigulatella and active compounds revealed. [ABSTRACT FROM AUTHOR]

LEAFMINERS, INSECT sex attractants, and PHEROMONES

Dodecyl acetate (12:OAc) (E)-10-dodecenyl acetate (E10-12:OAc) and (E)-10-dodecenol (E10-12:OH) in the ratio 8 : 80 : 12 were collected by solid phase micro-extraction of the volatiles emitted by virgin signalling females of the spotted tentiform leafminer moth, Phyllonorycter blancardella. The same compounds in the ratio 8 : 79 : 13 were extracted from the sex pheromone glands of virgin signalling females of the same species. The chemical structures of the compounds were identified by gas chromatography and mass spectrometry. Trapping results obtained from field tests using synthetic components of the sex pheromone demonstrated that only one component, E10–12:OAc, was essential for the attraction of conspecific males and should be considered as a sex pheromone. [ABSTRACT FROM AUTHOR]