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The experiments about the gas lift pump in lead-bismuth eutectic are performed with risers of three kinds of diameters [{phi}69.3 mm (SD case), {phi}106.3 mm (MD case), {phi}155.2 mm (LD case)]. The main results are as follows: (1) The coefficient of the drift flux model was derived from the experimental results. (2) The LBE flow rate obtained from the design method based on water/gas system with the relation of the drift flux model corresponds to the experimental results obtained in the MD and the SD cases. It is considered that the evaluation method can be used for the LBE gas lift pump in a small diameter riser. (3) In the LD, the design method excessively evaluates the lead-bismuth circulating flow rate. It thought that the circulation head will not occur in the experimental loop. The following factors are considered to be the causes of this: the three-dimensional behavior of bubbles becomes significant, and the local descending flow is generated in the riser when the riser diameter increases. (author)

The larval distribution and feeding habits of Cynoglossus abbreviatus and Cynoglossus lighti were investigated around the Rokkaku estuary in Ariake Bay during October 2004 and March and April 2005. Cynoglossus abbreviatus started and completed metamorphosis at larger sizes than C. lighti. Developmental phases consisted primarily of individuals at metamorphosis and postmetamorphosis, which were mainly distributed inside and just outside the Rokkaku River in March–April for C. abbreviatus and October for C. lighti. Tidal changes in vertical distribution just outside the river mouth differed between the closely related species; C. abbreviatus was distributed in the surface and middle layers at flood tide, and aggregated near the bottom (where the current speed was lowest) at ebb tide. Cynoglossus lighti stayed mainly near the bottom during all tidal phases. Larvae of both Cynoglossus species selectively fed on copepods (Pseudobradya sp.), which were scarce in the waters. These facts suggest that the nursery grounds of the two Cynoglossus species were different in terms of their tidal vertical distribution patterns.

The total Nusselt number increases with decreases in: (i) the conduction-radiation ratio contribution and (ii) the number of intermediate plates.

A total of 211 larval and juvenileNibea mitsukurii (4.0–19.0 mm SL) was collected with a small seine in surf zones of Tosa Bay during the period of May 1981 to June 1984. They had morphological characteristics common to the larvae and juveniles of Sciaenidae, but were distinguished from the others by the distribution pattern of melanophores on body and spines at the anterior tip of maxillary. They occurred only in surf zone of Tei out of three locations facing Tosa Bay from middle May to middle August. Temperatures and salinities at the place when they were collected ranged from 21.7 to 29.5°C and from 24.5 to 31.3‰, respectively. Good catches were observed when minute dusts floated abundantly in the surf zone. In past studies using traditional larval nets or minnow-nets in coastal or shallow waters of Tosa Bay, larval and juvenileN. mitsukurii were not reported. It seems that they occur in association with minute dusts in extremely shallow waters such as surf zones.

A total of 343 larval and juvenile Lateolabrax latus (9.2–27.0 mm TL) was collected with a small seine in surf zones of Tosa Bay. They are very similar in general morphology to those of the closely related L. japonicus, but can be distinguished from them by the distribution pattern of melanophores on the tail, head spination, proportion of head length to standard length and the 15 or 16 dorsal fin soft-rays. They occurred in surf zones of Tosa Bay from early January to middle May, being most abundant in middle April. Temperatures and salinities of waters where any number of them were collected ranged from 12.2 to 24.0°C and from 23.7 to 34.5%, respectively. Larval and juvenile L. latus have not been reported so far in coastal and shallow waters, and eelgrass beds of southern Japan. It may be possible that they have been confounded with those of L. japonicus. Their occurrence seems to be limited in extremely shallow waters such as surf zones.

A total of 515 larval and juvenileSparus sarba (8.2–17.8 mm TL) was collected at semimonthly intervals with a small seine in surf zones of Tosa Bay during the period of May 1981 to May 1982. They had morphological characteristics common to the larvae and juvenile of Sparinae, but were distinguished from the others by 24 dorsal and 14 anal fin rays, the first soft ray of pelvic fin not elongated and small melanophores along the dorsal margin occurring first on the caudal peduncle. They occurred in surf zones of Tosa Bay in two separate seasons, from late March to late May, and from late November to late January, being most abundant in April and May. In past studies using traditional larval nets or minnow-nets in coastal or shallow waters of Tosa Bay, larval and juvenileS. sarba were not reported. It seems that their distribution is limited in extremely shallow waters such as surf zones.

Fish larvae and juveniles were collected in the waters of wading depth along sandy beaches of western Japan with a 0.7-mm-mesh, 1.3- by 5-m seine. Presence of Chanos chanos, Salangichthys microdon, Plecoglossus altivelis, Allanetta bleekeri, Gerres oyena, Sparus sarba, Acanthopagrus schlegeli, A. latus, and Lateolabrax latus and absence of Engraulis japonica, Gonorhynchus abbreviatus, Upeneus bensasi, and Macrorhamphosus scolopax distinguished the larval ichthyofauna of surf zones from those in other known biotopes of fish nursery. The surfichthyofauna was usually more diverse in spring and summer than in autumn and winter. Monthly total catches of individuals fluctuated greatly according to the abundances of a few influential species such as Clupanodon punctatus in spring and Plecoglossus altivelis in autumn to winter. Most larval fishes seemed to inhabit surf zones only during daytime. An influence of tidal phases on occurrence of larval fishes was not apparent. Categories of pelagic and demersal components were suggested for surf zone ichthyofauna., Transactions of the American Fisheries Society: Vol. 114, No. 4 pp. 609?618; 1985

Larvae and juveniles ofLateolabrax japonicus andL. latus occurred from January to May 1986 in the shallow waters of the Shimanto estuary.L. japonicus markedly outnumberedL. latus. Distinct ecological differences were recognized in habitats and food habits between the two species:L. japonicus mainly inhabited eelgrass beds composed ofZostera nana, whileL. latus appeared evenly in both eelgrass beds and non-eelgrass habitats; the former fed on copepods and cladocerans, while the latter fed on copepods and fish larvae. From these habitat and food habit analyses, estuaries were considered to be important as a main habitat forL. japonicus, but not forL. latus. The fact that ecological differences have occurred during the early life stages was inferred to be one of the possible keys to speculate on the speciation of the two species.

The Chebyshev polynomial expansion of the source function is presented to analyze the combined conductive and radiative heat transfer in an optically thick porous body. Better agreement between the theory and the experiment is shown concerning the temperature profiles and the heat transfer characteristics of cordierite porous bodies. This analytical method is also applied to the examination of the Rosseland approximation to radiative transfer in an isotropically scattering medium, and consequently it is revealed that the Rosseland approximation is valid in the range of optical thicknesses greater than 200. Moreover, it is suggested that in the case of ceramic porous bodies possessing a three-dimensional netted structure an increase in the equivalent extinction coefficient and a decrease in the tortousity-discontinuity factor are much conducive to improvement of their thermal performance as thermal insulators.

A detailed analytical model to explain the vapor film collapse was developed to evaluate the occurrence conditions of self-triggering vapor explosions. The following conclusions were drawn based on linear stability analysis using the thermo-physical property of water, by linearizing and perturbing basic equations (Rayleigh-Lamb-Plesset's bubble momentum equation, the mass conservation equation, the state equation for ideal gas, and the Clausius-Clapeyron equation). The vapor film stabilizes with the reduction of the hot-liquid diameter, decrease of the condensation heat transfer coefficient, or increase of the thermal radiation coefficient. The cold-liquid viscosity and surface tension have a stabilizing effect, though this effect is negligibly small when the hot-liquid diameter is over 1 mm. The analysis predicts the vapor explosion occurrence limits obtained experimentally by other researchers within approximately 10 K. A simple correlation for the stability boundary is proposed by simplifying the above...