Rapid detection of drugs in biofluids using atmospheric pressure chemi/chemical ionization mass spectrometry

We have demonstrated that, with simple pH adjustment, volatile drugs such as methamphetamine, amphetamine, 3,4‐methylenedioxymethamphetamine (MDMA), ketamine, and valproic acid could be analyzed rapidly from raw biofluid samples (e.g. urine and serum) without dilution, or extraction, using atmospheric pressure ionization. The ion source was a variant type of atmospheric pressure chemical ionization (APCI) that used a dielectric barrier discharge (DBD) to generate the metastable helium gas and reagent ions. The sample solution was loaded in a disposable glass pipette, and the volatile compounds were purged by nitrogen gas to be reacted with the metastable helium gas. The electrodes of the DBD were arranged in such a way that the generated glow discharge was confined within the discharge tube and was not exposed to the analytes. A needle held at 100–500 V was placed between the ion‐sampling orifice and the discharge tube to guide the analyte ions into the mass spectrometer. After pH adjustment of the biofluid sample, the amphiphilic drugs were in the form of a water‐insoluble oil, which could be concentrated on the liquid surface. By gentle heating of the sample to increase the evaporation rate, rapid and sensitive detection of these drugs in raw urine and serum samples could be achieved in less than 2 min for each sample. Copyright © 2009 John Wiley & Sons, Ltd.     

A New Route to Resorcinols

A convenient preparation of resorcinol derivatives from α-phenylsulfinyllactones and α, β-unsaturated ketones is described.     

Theoretical approaches to the mechanical relaxation mechanisms in semicrystalline polymers

Two kinds of relaxation mechanisms in semicrystalline polymers, i.e., the primary relaxation mechanism attributed to the noncrystalline phase and the crystalline relaxation mechanism attributed to the crystalline phase, are explained, respectively, in terms of (1) a modified Bueche's model of a one-dimensional vibrating string taking higher-order potential effects into account and (2) Montroll's model of a plane lattice in the form of a vibrating membrane. The modified Bueche's theory of a one-dimensional vibrating string gives a slope in the wedge portion of the relaxation time spectrum of less than – 1/2, when one assumes that the force constants of higher-order potential effects of intra- and intermolecular interaction are negative. The plane lattice model of a membrane vibrating in a lateral as well as in a longitudinal fashion gives a box-type relaxation time spectra over almost the same relaxation time range.     

Reduction of grown-in dislocation density in Ge Czochralski-grown from the B2O3-partially-covered melt

Germanium (Ge) single crystals with an extremely low density of grown-in dislocations were grown by the Czochralski (CZ) technique with boron oxide (B₂O₃) liquid. Because attachment of particles floating on the melt surface to a growing Ge crystal leads to generation of dislocations during the growth, partial covering of the Ge melt surface with B₂O₃ liquid was attempted. Such attachment of particles was drastically suppressed or the particles were caught by the introduction of B₂O₃ liquid, and a particle-free Ge melt was realized in the central region of the melt surface. Ge single crystals were successfully grown from such melt, the grown-in dislocation density being 0–1×10³ cm⁻², which was remarkably lower than that in Ge crystals grown by a conventional CZ technique. The contaminations by B and O atoms of the grown crystal detected by SIMS analysis were very low. These Ge crystals have the potential for application to be applied as high-quality, dislocation-free substrates of GaAs solar cells for various usages including in space.     

Molecular weight dependence of fiber structure development in the laser drawing of poly(ethylene terephthalate) fibers

The effect of molecular weight on fiber structure development during the continuous neck‐drawing of the amorphous poly(ethylene terephthalate) (PET) fiber was investigated by fiber temperature measurements and online WAXD analysis. The fiber temperature was also simulated using the energy balance equation. The simulated temperature increased differently with molecular weight immediately after the neck point, while the measured temperature showed no difference. The difference in the simulated temperature was caused by the potential energy increase with increasing molecular weight, which would result in a retardation effect in the initial stage of fiber structure development. Online X‐ray measurements were carried out with a time resolution of 0.5 ± 0.06 ms. A two‐dimensionally ordered mesophase was formed within 1 ms after the neck point and developed into a microfibrillar structure. The time required for the disappearance of the two‐dimensionally ordered structure increased with increasing molecular weight, leading to a retardation effect. No molecular weight dependence was observed in the rate of transformation from the two‐dimensionally ordered structure to the PET crystal. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1653–1665, 2009     

Development and applications of “Mössbauer cameras”

Two different types of “Mössbauer camera” are presented in this review article. The first one uses an imaging technique for γ-rays which are converted to visual light by a Photon-counting Image Acquisition System (PIAS) combined with a Fiber Optic plate with CsI (Tl) Scintillator (FOS), while the second one is a mapping technique for γ-rays which are first focused by a Multi Capillary X-ray lens (MCX), and subsequently electrons and γ-rays are detected as function of the sample position by a micro-channel plate (MCP) and a Si-PIN detector, respectively. A mapping image of a silicon solar cell is shown as an example obtained by the latter system. We also report on the present status in developing a new combined lens for the mapping using a MCX and a Fresnel Zone Plate (FZP) in order to realize a submicron-meter spatial resolution in a laboratory.     

Rhenium complex-catalyzed allylation of acetals with allyltrimethylsilane

It was confirmed that the treatment of acetals with allyltrimethylsilane in the presence of a catalytic amount of the rhenium complex, ReBr(CO)₅, gave the corresponding homoallylic ethers in excellent to good yields.