A nuclear magnetic resonance (NMR) probe and spectrometer capable of investigating full intact wine bottles is described and used to study a series of Cabernet Sauvignons with high resolution 1 H NMR spectroscopy. Selected examples of full bottle 13 C NMR spectra are also provided. The application of this full bottle NMR method to the measurement of acetic acid content, the detection of complex sugars, phenols, and trace elements in wine is discussed.

French prune trees provide overwintering habitat for the egg parasitoid Anagrns epos Girault (Hymenoptera: Mymaridae), an important natural enemy of the the grape leafhopper, Erythroneura elegantula Osborn (Homoptera: Cicadellidae). French prune trees were treated with rubidium during the fall of 1991-1993 to assess the potential for obtaining an elemental label in overwintering A. epos. Multiple applications of 5,000-ppm solutions of RbCI to French prune foliage from late August to early October resulted in increases in foliar rubidium content of up to 200 times the naturally occuring concentration. Rubidium content of adult prune leafhoppers, Edwanuiana prnnicola Edwards (Homoptera: Cicadellidae), collected from treated trees was up to 130 times the naturally occurring level. Naturally occuring rubidium content of A. epos was 0.052 ng Rb per individual based on a sample of 498 wasps collected from 3 separate, untreated grape vineyards. Mean rubidium content was 0.205 ng Rb in A. epos collected in the spring directly from French prune trees that had been treated in the fall with RbCI. This is 3.9 times the background level and indicates successful labeling of overwinteringA. epos. However, there was substantial overlap in rubidium content between A. epos from treated trees and those from untreated sites. A. epos reared from rubidiumenriched host eggs and maintained in the lab on a mixture of honey and water e1iliibited minimal decay of the elemental label during the adult lifetime. Success of this labeling approach has made possible the direct study of the dispersal of A. epos from treated French prune tree refuges into adjacent grape vineyards.

The compounds Ca 14 AlP 11 , Ca 14 MnP 11 , and Eu 14 MnP 11 have been synthesized and are isostructural to the Zintl compound, Ca 14 AlSb 11 . Eu 14 MnP 11 is a ferromagnet showing colossal magnetoresistance at T C ) 52 K, Ca 14 MnP 11 shows paramagnetic behavior down to 5 K, and Ca 14 AlP 11 is nonmagnetic. The formula unit for these Zintl compounds is A 14 MPn 11 and comprises 14 A cations, a MPn 4 tetrahedron, four isolated Pn anions, and a Pn 3 linear unit. The central Pn of the Pn 3 unit is believed to be positionally disordered, and it has been speculated that the disorder is static rather than dynamic. To address this issue, 31 P solidstate NMR was applied to these new compounds to provide insight into the magnetic ordering and structural changes. The NMR chemical shift anisotropy and the dipolar coupling for the 31 P nuclei as well as the quadrupolar coupling for the 27 Al nucleus in the diamagnetic compound Ca 14 AlP 11 provide structural details consistent with the Zintl structure. Wideline 31 P NMR and EPR were applied to the paramagnetic compounds Ca 14 MnP 11 and Eu 14 MnP 11 to obtain similar structural information. The lack of any EPR spectra for the Eu-substituted compound below 50 K confirms the assigned paramagnetic-to-ferromagnetic transition temperature of 52 K. Hyperfine couplings in the Eu-substituted compound suggests localization of the electron density above 50 K.

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Multiple peak formation and interconversion in the liquid chromatographic (LC) analysis of triostin A and its under-N-methylated synthetic analogue, [N-MeCys3,N-MeCys7]-TANDEM (MCTANDEM), are investigated as a function of column temperature. Slow interconversion between chromatographic peaks, ascribed to the presence of the n- and p-solution conformers of the peptides, is exhibited in the normal-phase elution profiles of triostin A and in the reversed-phase elution profiles of MCTANDEM. A chromatographic model is developed to estimate the kinetics of conformer interconversion. Reversed-phase LC analysis of the n- and p-conformers of MCTANDEM yields a value of 0.01/s for the apparent interconversion rate constant (kn-p) at 25 degrees C, with a corresponding activation energy of 16 kcal/mol. Normal-phase LC analysis of the n- and p-conformer interconversion of triostin A dissolved in chloroform results in a value of 0.04/s for kn-p at 25 degrees C, with a corresponding activation energy of 18 kcal/mol. For triostin A, normal-phase LC findings as a function of column temperature are compared with 1H nuclear magnetic resonance (NMR) line-width measurements between 80 degrees C and 140 degrees C for the n- and p-conformers, which yield an activation energy of 19 kcal/mol and an extrapolated value of 0.02/s at 25 degrees C for kn-p in deuteriochloroform.