Determination of Inosine-5-Monophosphate in Fish Tissue with an Enzyme Sensor

An enzyme sensor for IMP consisted of immobilized enzymes and an oxygen electrode. A nucleotidase (E.C. 3.1.3.5.), nucleoside phosphorylase (E.C. 2.4.2.1.) and xanthine oxidase (E.C. 1.2.3.2.) were immobilized on a membrane prepared from cellulose triacetate, 1,8-diamino-4-aminomethyloctane and glutaraldehyde. Optimum conditions for IMP determination were pH 7.8, 30°C, a flow rate of 1 ml min⁻¹ and sample volume of 20 μl. A calibration curve for IMP was linear up to 15 mM. This sensor could be applied to the determination of IMP in meats of sea bass, mackerel, yellowfish and saurel. Good correlative results were observed between the values obtained by the sensor and the conventional method. The sensor was stable for more than 15 days at 5°C and 100 assays.     

Influence of Temperature and Humidity on Dynamic Fatigue of Optical Fibers

The influence of temperature and humidity on dynamic fatigue characteristics of silicone resin-coated optical glass fibers is examined. Dynamic fatigue is shown to result from subcritical crack growth. Test results verify that subcritical crack growth during dynamic loading is a thermally activated process and that the effect of humidity on crack growth is a function of water vapor pressure.     

Crack Growth in Silica Glass Under Dynamic Loading

A dynamic loading test at a slow strain rate was made to examine the stable crack-growth process in silica glass under several environmental conditions. The temperature and humidity influence on the crack-growth process was investigated in detail. Test results show that the transition from region I to region II occurs at a constant stress intensity factor, K , independent of temperature and humidity. The transition K value was determined to be 0.61 MPa.m^1/2. Furthermore, it is clear that the crack-growth rate is dependent on K , even in region II.     

Preparation of Submicrometer A12O3 Powder by Gas-Phase Oxidation of Tris (acetylacetonato) aluminum (111)

Fine A1₂O₃ powder was prepared by the gas-phase oxidation of aluminum acetyl-acetonate. The reaction products were amorphous material at 600° and 800°C, γ-Al₂O₃ at 1000° and 1200°C, and δ-Al₂O₃ at 1400°C. The powders consisted of spherical particles from 10 to 80 nm in diameter; particle size increased with increasing reaction temperature and concentration of chelate in the gas.