Synthesis of β-Si3N4 by Chemical Vapor Deposition

Beta-type CVD-Si₃N₄ plates (up to 1.1 mm thick) have been prepared by adding TiCl₄ vapor to the system SiCl₄-NH₃-H₂ at deposition temperatures of 1350° to 1450°C, while α-type or amorphous CVD-Si₃N₄ was obtained without TiCl₄ vapor at the same deposition temperature. Three to four wt % 777V was included in the β-type CVD-Si₃N₄ matrix. The density, preferred orientation, and lattice parameters of β-type CVD-Si₃N₄ were examined.     

Active control for the suspension of large-sized buses using fuzzy logic

An active suspension of large-sized buses by using fuzzy logic is considered. The active control for the suspension is determined by minimizing the mean squares of vertical and rotary accelerations of vehicle body subject to the constraints of suspension and tyre deflections. The vehicle model is assumed to be a linear system with six degrees of freedom excited by road profiles. The tuning of fuzzy control rules and associated parameters that characterize the active control is carried out where two kinds of road profiles are considered. In the simulation results, the proposed active suspension shows improved performance over passive suspension     

Entrance effect correction on the flow of moisturized soy protein isolate melt in an extrusion viscometer

A newly developed capillary viscometer, having an airtight sample cell and capillary system, was utilized to determine the flow properties of moisturized [70% dry basis (d.b.)] soy protein isolate (SPI) melt at 140°C. Pressure drop measurement with an orifice die was done to clarify the large end effect. An end effect correction method was performed by subtracting the orifice die data from the capillary tube data, and reasonable results were obtained. The flow properties of the SPI melt were thus elucidated and could be classified as those of a power law fluid with flow behaviour index of 0.35. It was concluded that SPI with 70% d.b. moisture is an extremely high pseudoplastic fluid at 140°C.     

Sensory Analysis of Taste-Active Components in the Extract of Boiled Snow Crab Meat

A synthetic extract, prepared from 44 pure chemicals on the basis of the analytical data on the leg meat extract of the boiled snow crab, Chionoecetes opilio, satisfactorily reproduced the taste of the natural extract except for a slight lack of body and mildness. A series of taste panel assessments on synthetic extracts prepared by omitting or adding extractive component(s) were carried out by a triangle difference test and changes in taste profile were assessed. Only 12 components, Ala, Arg, Glu, Gly, glycine betaine, AMP, CMP, GMP, Na⁺, K⁺, Cl^?, and PO₄^3-, were found to contribute more or less toward producing the characteristic taste of the snow crab.     

Novel Measurement of Hypoxanthine in Fish Using Direct Measurement Probe and Chemiluminescence Flow Injection Analysis

Direct measurements of hypoxanthine (Hx) in fish flesh were carried out using a sardine and a grunt twice with the same fish, and the average of 10 successive measurements (from 120 sec to 480 sec after pressing the probe against fish tissue) was taken as the Hx concentration by direct measurement. Results with two nearby tissues of one sample were 42.9 ± 4.9 μM and 42.6 ± 2.6 μM for the sardine, and 639 ± 33 μM and 598 ± 29 μM for the grunt. For sardine, Hx results from this direct method did not agree well with perchloric acid extraction measurements, but they were much better for grunt.     

Purification of Milk Catalase by Immunoaffinity Chromatography

Antiserum against commercially available bovine liver catalase was prepared in rabbits. Anti-catalase antibody in serum was prepared following 30% ammonium sulfate treatment and Sephacryl S-300 column chromatography. The anti-catalase antibody was coupled to cyanogen bromide-activated Sepharose 4B, and using this immunoadsorbent crude milk catalase was purified. About 7.0 mg pure catalase was produced from 10 kg milk. Activity of the purified products was about 2.58 × 10⁴ times as pure as cows' milk. The purified catalase was electrophoretically homogeneous, appearing as a single band.     

Relationship Between Static Electrical Conductivity and Unfrozen Water Content in Food Products

The static electrical conductivity measurements on frozen foods such as citrus juice and varieties of cheese showed that both conductivity and unfrozen water content in food products varied directly with temperature. In describing the log σ vs 1/T curve, where σ is the conductivity and T is the absolute temperature, it was found that the linear portion of the curves at low temperature was related to bound water content which was independent of temperature, whereas the non-linear portion in the temperature range between the freezing point and 10 or 35 degrees below the freezing point was related to the unfrozen free water content which was dependent on temperature.     

Milk Fat Globule Membrane Substances Inhibit Mouse Intestinal β-Glucuronidase

The β-glucuronidase inhibitory action of milk fat globule membrane (MFGM) was studied. By increasing the MFGM concentration to 0.2%, nearly 90% of the β-glucuronidase activity was inhibited. The trypsin-derived digests of MFGM inhibited β-glucuronidase activity by ～ 42%. The inhibitory effect of MFGM on intestinal β-glucuronidase of mouse was studied. We administered MFGM (groups I: 5%; group II: 10%; group III: 20%) to mice and investigated the time course of changes in fecal β-glucuronidase activity. In group I and II, enzyme activity had decreased 15–20% on the 5th day of treatment, but in group III, a decrease in enzyme activity was seen with an inhibition rate of 50%, showing a marked intracolonic efficacy of MFGM. Thus MFGM may have potential in explaining, treating or preventing intestinal cancers.     

Hydration of heat-treated soy protein isolate and its effect on the molten flow properties at an elevated temperature

The relationship between the flow properties of soy protein isolate (SPI) at 140°C, measured using an extrusion viscometer, and changes in the hydration state were investigated. The state of the water in SPI was analysed by measurement of the freezable water content using differential scanning calorimetry (DSC) and by spin-spin relaxation rate (R₂) measurements using pulsed nuclear magnetic resonance (NMR). The dependence of the flow properties on the state of water was indicated by the correspondence between the water content at which the flow characteristics of molten SPI changed, and the critical water content indicated by DSC measurement of the minimum freezable water content, and by the inflection point in NMR measurement of the spin-spin relaxation rate (R₂).