Ultrafast polarisation-independent all-optical switching using a polarisation diversity scheme in the nonlinear optical loop mirror

Polarisation-independent 32 to 8 Gbit/s demultiplexing in the nonlinear optical loop mirror is successfully demonstrated using a novel polarisation diversity scheme in which two independent switching operations are performed along the two principal axes of a polarisation-maintaining fibre loop. The variation of the switched signal powers is measured to be less than 1 dB as the input polarisation direction is varied over 180 degrees .<>     

Ischemic change of organic acids in kidney

Organic acids in rabbit renal tissue biopsy were analyzed by capillary column gas chromatography--mas s spectrometry. The change of these organic acids under ischemic conditions was determined over 60 min after clamping the renal artery and vein. The results showed that lactic acid, glycolic acid, 2-hydroxybutyric acid, 3-hydroxypropionic acid, 2-methyl-glyceric acid, glyceric acid and malic acid increased at 4 and 6 min after clamping, but then decreased at 15 min. Glycerol increased 2 min after clamping and then decreased. However, 3-deoxyaldonic acids of 3-deoxytetronic acid, 3-deoxy-2-C-hydroxymethyltetronic acid and 3-deoxypentonic acid decreased in the renal tissue biopsy from 2 min after clamping.     

Automating the measurement of the softening point of glasses using a gas laser

Viscous elongations of thin glass fibers have been automatically traced and recorded near their softening points using an optical, mechanical, and electronic method. The technique allows tracing to be obtained by applying external forces of less than 5 mg. Measurements were repeatable to within ±1−2°C; this repeatability was critically dependent on the uniformity of the glass fibre diameter.     

High-speed bi-directional polarisation division multiplexed opticaltransmission in ultra low-loss (1.3 dB/km) polarisation-maintainingphotonic crystal fibre

A high-speed optical transmission experiment was successfully demonstrated in an ultra low-loss polarisation maintaining photonic crystal fibre. The fibre loss and modal birefringence at 1550 nm were 1.3 dB/km and 1.4×10^-3, respectively. A 10 Gbit/s bi-directional optical signal was successfully transmitted through the 1.5 km fibre     

Reaction and sensing of octafluorocyclopentene with 1,5-diazabicyclo[4,3,0]non-5-ene

Reactions of octafluorocyclopentene (C₅F₈) with 1,5-diazabicyclo[4,3,0]non-5-ene (DBN) are studied by analyses of an isolated product and optical spectra from the viewpoint of applications to gas-sensors. Obtained results suggest that nucleophilic reactions of DBN proceed toward the double bond of C₅F₈ molecule accompanied with hydroxide anion attack on carbon-fluoride bonds of C₅F₈ moiety under ambients, forming unique C₅F₈-modified adducts. The present reaction is conducive to a new type of technologies for quick and selective sensing that can be used to develop alarm systems in the field of the environment and etching processing factories.     

Ionophoretic activities of oligopeptide lactones and resin-glycosides in human erythrocytes

Oligopeptide lactones (theonellapeptolides) isolated from the Okinawan marine sponge Theonella swinhoei and resin-glycosides (merremosides) from the tuber of an Indonesian medicinal plant Merremia mammosa were examined regarding their activities in transporting Na+, K+, and Ca++ ions into human erythrocytes. Each of these lactones, which had been shown, using a supported liquid membrane, to have an ionophoretic effect on the alkali metal ions, transported the ions to a different extent. The ion transporting activities of these compounds were completely lost when the macrocyclic lactone structures were cleaved by sodium methylate. Resin-glycosides with an additional branched glycosyl residue showed much greater ion transporting activities than those without it.     

100 Gbit/s, 50 km, and nonrepeated optical transmission employing all-optical multi/demultiplexing and PLL timing extraction

A 16*6.3 Gbit/s, time-and-polarisation division multiplexed optical signal is successfully transmitted through a 50 km dispersion shifted singlemode fibre employing all-optical multi/demultiplexing. A 6.3 GHz timing clock is directly extracted from the multiplexed 100 Gbit/s optical signal by a phase locked loop (PLL) using a travelling-wave laser diode amplifier. A wavelength-tunable modelocked Er/sup 3+/-fibre ring laser and a planar-lightwave-circuit time division multiplexer are newly developed for this experiment.<>