High-resolution mass spectrometry was used to measure a range of volatile organic compounds (VOCs) in real time as they were produced by the ubiquitous marine cyanobacterium Synechococcus WH8102 during a 24-hour light/dark cycle. Ethenone, acetaldehyde, ethanol, isoprene, acetic acid, dimethyl sulfide (DMS), acetone, phenol, and several as-yet unidentified compounds were...
The inert gas ion bombardment of solid surfaces has
found many uses in the field of analytical chemistry. In
one method of spectrochemical analysis, inert gas ion
bombardment in a glow discharge is used to produce an atomic
vapor, representative of the sample bulk, which is analyzed
using atomic absorption...
The surface areas and pore size distributions of a
series of terrigenous marine sediments were measured by gas
adsorption. The sediment samples were taken from the continental
terrace off the coast of Oregon near Newport.
Sampling stations ranged up to 35 miles off shore between
44°20' and 45° north latitude....
The observed and calculated structural parameters of three systems
of phosphatidylcholine bilayers in fully-hydrated multilamellar
vesicles (MLVs) were determined using x-ray diffraction techniques.
The analysis used the x-ray reflections from the low-, intermediateand
wide-angle regions of the diffraction patterns in the subgel, gel,
rippled and fluid phases to determine the...
Lamellar x-ray diffraction was studied from thin films of L-α-1,2-dipalmitoyl lecithin (DPL) and a 1:1 mixture (BrDPL) of L-α-l-palmitoyl-2-(9- bromopaimitoyl) lecithin and its 10-bromo analog. The specimens had high lamellar order, with an upper bound on the mosaicity of 6 mrad (0.4°) for DPL and BrDPL. With various water contents,...
A high-spectral resolution laser-excited molecular fluorescence
system was developed that utilizes a pulsed supersonic expansion to
simplify the fluorescence excitation spectra of large, gas-phase
aromatic molecules diluted in an excess of a monatomic gas. A
microcomputer was used to control and synchronize the instrumental
components, which included a Chromatix CMX-4...
Complex organic transformations, such as the addition of pyrrole to ketene using planar chiral organocatalyst (*PPY), the four-component anhydride- Manniach reactions, and the site-selective desymmetrization of meso-1,2-diol, are remarkable synthetic reactions that provide high yield and high selectivity. However, the exact mechanism and origins of stereocontrol for theses synthetic organic...