Qualitative and quantitative gas liquid chromatography of triglycerides.

This article reviews the methodology required for triglyceride analysis by gas liquid chromatography. Compositions of the animal and vegetable triglyceride mixtures to which this technique has been applied are summarized.     

Theoretical analysis and experimental investigation of pulsed tunable forsterite laser

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Neutron reflectivity study of adsorbed diblock copolymers

Summary In this paper, we summarize our cumulative work on neutron reflectivity studies of polystyrene-poly(vinyl-2-pyridine) (PS-PVP) and polystyrene-polyethylene oxide (PS-PEO) adsorbed at a quartz-solvent interface. Deuterated toluene was chosen as the solvent since it is a good solvent for PS and a poor one for either of the other two blocks. In this case, the polystyrene dangles into the solvent while the other block acts as an anchor. The neutron reflectivity studies reveal that the form of the polymer density profile normal to the substrate may be varied from an extended ?brush? to a condensed ?mushroom? conformation by manipulating the ratio of the molecular weights of the two blocks. In addition, we present new data on the PS-PEO system in a poor solvent, deuterated cyclohexane, under conditions of shear flow in Poiseuille geometry. We find that when the PS-PEO diblock is absorbed from cyclohexane and is allowed to relax, the PS chain takes on a ?mushroom? conformation. However, when the shear is applied, the layer shear thickens due to the PS chains extending to nearly twice their original lengths. Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994.     

Optical bistability in a gaussian cavity mode

The mean field treatment of dispersive and absorptive bistability for two-level atoms in an optical cavity is extended to account for the gaussian envelope of the cavity mode. The principal modification to the plane wave cavity case is the raising of the critical threshold for absorptive bistability as compared to thresholds for dispersive bistability.     

Aryl substituent effects upon the thermal isomerization of n-alkyl oxaziridines to nitrones

The results of a kinetic study of the thermal isomerization of oxaziridines derived from $\text{para}$-substituted C-arylaldimines and C-diarylketimines to the isomeric nitrones is reported.     

Weak localization, hole-hole interactions, and the "Metal"-insulator transition in two dimensions

A detailed investigation of the metallic behavior in high-quality GaAs-AlGaAs two-dimensional hole systems reveals the presence of quantum corrections to the resistivity at low temperatures. Despite the low density ( r(s)>10) and high quality of these systems, both weak localization (observed via negative magnetoresistance) and weak hole-hole interactions (giving a correction to the Hall constant) are present in the so-called metallic phase where the resistivity decreases with decreasing temperature. If these quantum corrections persist down to T = 0, the results suggest that even at high r(s) there is no metallic phase in two dimensions.     

A Facile Route to Group 13 Difluorodiorganometalates:

A facile synthesis utilizing tetra-n-butylammonium hydrogen difluoride and Group 13 alkyl compounds leads to the soluble salts 1 - 4. Compound 1 is the smallest difluoro-diorganoaluminate so far characterized. The corresponding gallium and indium derivatives 3 and 4 are not sensitive to moisture.