CAUSAL FUNCTIONAL REPRESENTATION LANGUAGE WITH BEHAVIOR-BASED SEMANTICS

Understanding the design of a device requires both knowledge of the general physical principles that determine its behavior and knowledge of its intended functions. However, the majority of work in model-based reasoning has focused on using either one of these types of knowledge alone. In order to use both types of knowledge in understanding a device design, one must represent the functional knowledge in such a way that it has a clear interpretation in terms of observed behavior. We propose a new formalism, causal functional representation language (CFRL),for representing device functions with well-defined semantics in terms of behavior. CFRL allows the specification of conditions that a behavior must satisfy, such as occurrence of temporal sequences of events and causal relations among them and the components. We have used CFRL as the basis for afunctional verification program, which determines whether a behavior achieves an intended function.     

EFFECT OF ALKYL CHAIN LENGTH OF 3-ALKYLPENTANE-2, 4-DIONE ON THE EXTRACTION OF COPPER

The equilibrium and kinetics of the extraction of copper with 3-alkylpentane-2, 4-dione (-H, -C₂H₅, -Ph, and -C₈H₁₇) were studied. It was found that the overall equilibrium constant is related to the proton disscoiation constant and that the ratio of the stability constants of the copper chelate, β₂/β₁ ²was independent of the alkyl chain length of the β-diketone. The rate constants for the reactions between cupric ion and the β-diketones in the aqueous phase were obtained by the relaxation method. The values decreased in the order -H>-Ph>-C₂H₅. The observed extraction rates were explained by a kinetic model using the measured physicochemical properties.     

Histological Changes in High-Pressure-Frozen Carrots

Histological changes in carrots frozen using a computer-programmed high pressure pilot unit for food processing were examined by light microscope. When raw carrots were frozen at 50 MPa, – 15°C; 100 MPa, –15°C; 150 MPa, –25°C; 200 MPa, –28°C, they were extremely damaged due to volume expansion by the formation of ice I. Conversely, carrots pressurized at 100 MPa, – 10°C (between liquid phase and ice I) and 200 MPa at –20°C (liquid phase) were not damaged because they were frozen rapidly during pressure reduction. They were not damaged even after pressurizing-then-immersing in LN₂. Carrots frozen at 240 MPa, –28°C and at 280 MPa, –25°C, were also not damaged, although ice III formed. The structure of carrots frozen at 400 MPa, –20°C (ice V) was comparatively intact. When carrots were preheated at 60°C for 30 min and frozen at 100 MPa, –15°C or at 400 MPa, –20°C, damage was reduced further.     

Structural and Textural Changes in Kinu-Tofu Due to High-Pressure-Freezing

To determine the effect of high-pressure-freezing on quality, kinu-tofu (soybean curd) was frozen at 100 MPa (ice I), 200 MPa (liquid phase), 340 MPa (ice III), 400, 500, 600 MPa (ice V) or 700 MPa (ice VI) at ca. –20°C for 90 min. After reduction to atmospheric pressure, tofu was stored 2 days at –30°C then thawed at 20°C. Texture and structure were compared with kinu-tofu frozen (–20°C, –30°C or –80°C) at atmospheric pressure (0.1 MPa). The rupture stress and strain of tofu frozen at 0.1 MPa and 100 MPa increased, but that of tofu frozen at 200 MPa and 340 MPa was similar to untreated tofu. As pressure rose above 500 MPa, rupture stress increased. The ice crystals in tofu frozen at 200 MPa ～400 MPa were smaller than in tofu frozen at 100 MPa or 700 MPa. Thus, high-pressure-freezing at 200 MPa ～400 MPa was effective in improving the texture of frozen tofu.     

Clarification of Spray-Dried Egg Yolk Suspensions and Solubilization of Proteins from Lipoproteins

The separation of proteins and lipids from spray-dried egg yolk was attempted using commerical enzymes and mold enzymes. Good solubilization of protein from a spray-dried egg yolk suspension (clarification of the suspension), could not be obtained with purified commercial enzymes (protease, lipase and phospholipase), but three crude enzymes extracted from molds and one commercial enzyme produced good results. Among them, Newlase F (crude preparation, derived from the genus Rhizopus) successfully clarified the spray-dried egg yolk suspension (pH 4.7, 40°C, 5–8 hr), thereby solubilizing about 85% of the total protein in the whole spray-dried egg yolk.     

High-Pressure-Freezing Effects on Textural Quality of Carrots

Raw or 3 min blanched carrots were pressurized for 45 min at ?18°C ～–20°C and then thawed at 20°C. When carrots were frozen at 100Mpa (ice I), firmness decreased and strain increased. Textural values of carrots pressurized at 200MPa (liquid), 340MPa (ice III), 400MPa (ice V) at ca. –20°C were acceptable. When pressure was increased above 500MPa, the strain increased. Release of pectin and histological damage in carrots pressurized at 200, 340 and 400MPa were less than carrots frozen at 100 and 700MPa (ice VI). After pressurization at 200 and 340MPa at —20°C, carrots were stored in a freezer (–30°C). Firmness decreased and strain increased, but textural values were higher and histological structure were more intact than those frozen at –30°C (0.1MPa) then stored. Thus, high-pressure-freezing at 200, 340 and 400MPa appeared to be effective in improving both the texture and histological structure of frozen carrots.     

Pectic Substance Degradation and Texture of Carrots as Affected by Pressurization

Heated pectin was degraded by transelimination (β-elimination) above pH 5 and by hydrolysis below pH 2, but pressurized pectin did not degrade. Thus cooked carrots decreased in firmness, but pressurized carrots did not. Pressurizing above 200 MPa slightly increased rupture strain. Galacturonic acid levels decreased in carrots cooked for 30 min. Total pectin in pressurized carrots was the same as in cooked for 3 min. However, with increased pressure, the amount of high methoxyl pectin in carrots decreased while low methoxyl pectin increased. Thus, the effects of pressurization on pectin degradation (transelimination) and texture of carrots were different from those of heating.