L Tanks (l + tank)

Distribution by Scientific Domains


Selected Abstracts


Preliminary evaluation of the performance of an adsorption-based hydrogen storage system

AICHE JOURNAL, Issue 11 2009
Marc-André Richard
Abstract Using modeling and thermal simulations, the feasibility of an adsorption-based hydrogen storage system for vehicles is evaluated. The storage capacity of a 150 L tank filled with a high surface-area activated carbon is mapped for temperatures from 60 to 298 K and pressures up to 35 MPa. The thermal simulations are verified using experiments. For a storage capacity target of 5 kg, the adsorption-based storage system will offer a storage advantage over the cryogenic gas storage if the residual mass of hydrogen in the tank is retrieved by heating. For a discharge rate of 1.8 g/s, the required heat is of the order of 500 W. The net energy requirements for the refueling has contributions from compression, precooling and tank cooling and can approach that for liquid hydrogen storage. With a good insulation and a maximum tank pressure of 35 MPa, the dormancy period can be extended to several weeks. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]


The effect of protein levels on growth, postprandial excretion and tryptic activity of juvenile mullet Mugil platanus (Günther)

AQUACULTURE RESEARCH, Issue 4 2010
Cristina V A De Carvalho
Abstract The objective of the present work was to determine the optimum dietary protein level for juvenile mullets. Five isocaloric diets were formulated to contain increasing levels (300, 350, 400, 450 and 500 g kg,1) of crude protein (CP) corresponding to 18.7 MJ metabolizable energy kg,1. All diets were tested in triplicate. Each experimental unit was composed of a 50 L tank with 50 juveniles (mean ± SE initial weight and length equal to 1.17 ± 0.02 g and 4.34 ± 0.03 cm respectively). Diets were offered five times a day until apparent satiation for 35 days. No significant difference (P>0.05) was observed in survival rate, feed efficiency and body composition between treatments. However, weight gain, feed consumption and specific growth rate were higher in fish fed the 350 g kg,1 CP level than those fed the highest protein content diet (500 g kg,1 CP). The amount of postprandial ammonia excreted by mullet was linearly related to protein intake. Intestinal tryptic activity was inversely proportional to the percentage of dietary CP. It is likely that diets containing <350 g kg,1 CP will be needed for on-growing mullet, especially when reared in ponds with abundant natural food. [source]


Effects of Light Intensity and Salinity on Growth, Survival, and Whole-Body Osmolality of Larval Southern Flounder Paralichthys lethostigma

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2003
James P. Henne
The southern flounder Paralichthys lethosligma is a high-valued flatfish found in estuarine and shelf waters of the south Atlantic and Gulf coasts of the United States. Wide temperature and salinity tolerances exhibited by juveniles and adults make it a versatile new candidate for commercial culture, and studies are underway in the southeastern U.S. to develop hatchery methods for this species. The objectives of this study were to establish illumination and salinity conditions that optimize growth and survival of larval southern flounder reared through the yolk-sac and first feeding stages to 15-d post-hatching (15 dph). Early embryos were stocked into black 15-L tanks under light intensities of 5, 50, 100, and 1,000 Ix and at salinities of 24 and 34 ppt in a 4 ± 2 factorial design. Significant (P 0.05) effects of both light intensity and salinity on growth and survival were obtained, with no interaction between these effects. On 11 dph and 15 dph, growth was generally maximized at the intermediate light intensities (50 and 100 Ix) and minimized at the extremes (5 and 1,000 Ix). By 15 dph, growth was higher at 34 ppt than at 24 ppt. Survival to 15 dph showed trends similar to those of growth. Survival was higher at 100 Ix (avg. = 46%, range = 41,54%) than at 5 Ix (avg. = 11%, range = 6,17%) and higher at 34 ppt (avg. = 43%, range = 3145%) than at 24 ppt (avg. = 17%, range = 8,38%). Whole-body osmolality (mOsmol/kg) was significantly lower in larvae reared at 24 ppt (avg. = 304, range = 285,325) through 11 dph than in larvae reared at 34 ppt (avg. = 343, range = 296,405). Larvae reared under the extreme light intensity treatments (5 and 1,000 Ix) at 34 ppt appeared to exhibit osmoregulatory stress, particularly on 11 dph, when a marked increase in whole-body osmolality was observed. The mid-intensity treatments (50 and 100 Ix) at 34 ppt optimized growth and survival of larval southern flounder in this study; and elicited the most stable osmotic response. These conditions appear to be consistent with those that southern flounder larvae encounter in nature during this early developmental period. [source]


Effects of Amylopectin/Amylose Starch Ratio on Growth, Body Composition and Glycemic Response of Sunshine Bass Morone chrysops × M. saxatilis

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2003
Steven Rawles
Manipulation of the ratio of amylopectin (,-[1,4] and ,-[1,6] linked glucose) to amylose (,-[1,41 linked glucose) starches in the carbohydrate fraction of the diet has been used to improve carbohydrate and lipid metabolism in mammalian models. A 10-wk feeding trial was conducted to determine the effect of dietary amylopectin/amylose ratio on growth and composition of growth of advanced sunshine bass (Morone chrysops × M. saxatilis) fingerlings (60 g, initial weight). Fish were fed cold-pelleted, semipurified, isonitrogenous (35% crude protein), isocaloric (3.6 kcaVg protein), isolipidic (5%) diets containing 25% carbohydrate. The carbohydrate fraction of the diets was composed of either glucose, dextrin, 100% amylopectin/0% amylose, 70% amylopectin/30% amylose, or 30% amylopectin/70% amylose. Diets differing in ratios of amylopectin/amylose were achieved by adjusting the proportion of high-amylopectin (100% amylopectin) to high-amylose (70% amylose) corn starch. Diets were fed to fish in quadruplicate 76-L tanks (seven fish/tank) connected to a brackish water (5-7%v) recirculating culture system with biofiltration. Weight gain ranged from 195 to 236% of initial weight (60 g) and was significantly greater (P < 0.1) for fish fed diets containing 25% carbohydrate as dextrin or as 70% amylose and significantly lower in fish fed diets in which carbohydrate was composed of 30% amylose, 100% amylopectin, or glucose. Feed efficiency ranged from 0.52 to 0.61 and was higher in fish fed the diet containing the highest concentration of amylose and lower in fish fed the diet containing glucose. Hepatosomatic index was highest (2.71) in fish fed the diet containing glucose and lowest (1.401.45) in fish fed diets containing high-amylose cornstarch. Intraperitoneal fat ratio was distinctly lower in fish fed diets containing some amylose as compared to those fed diets without amylose. Liver lipid was significantly lower (4.8%) in fish fed the diet containing glucose and almost twice as high (7.3-8.9%) in fish fed the diets containing any starch. Glycogen content of the liver decreased from approximately 12% in fish fed the diet containing glucose to 5% in fish fed the diets containing amylose. Muscle proximate composition and ratio were unaffected by the dietary treatments. Fasting levels (15 h) of blood glucose in fish reared for 10 wk on the diet containing glucose were significantly elevated (5.5 mmol/L) when compared to fasting levels of those that had been reared on diets containing starch (3.4-1.1 mmol/L). Fish fed the diet containing glucose exhibited maximum blood concentrations (14.6 mmoVL) 4 h postprandial then rapidly declined to nearly fasting levels within 8 h postprandial. In contrast, maximum plasma glucose concentrations in fish fed diets containing starch were roughly half (6.8-8.1 mmol/L) those of fish fed the diet containing glucose. Blood glucose in fish fed diets containing dextrin or predominantly amylopectin starch remained elevated longer than that of fish fed diets containing glucose or predominantly amylose starch. Glycemic response appeared to decrease with increasing dietary amylose content. These data suggest that feeding diets in which a greater portion of the starch is amylose may be a useful strategy for improving carbohydrate use in sunshine bass. [source]


The Effect of Temperature on First Feeding, Growth, and Survival of Larval Witch Flounder Glyptocephalus cynoglossus

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2001
Deborah A. Bidwell
Witch flounder Glyptocephalus cynoglossus has recently been identified as a candidate species for aquaculture in the northeastern United States and the Canadian Atlantic Provinces. This study investigated the optimal temperatures for witch flounder larval first feeding and for long term larval culture from hatching through metamorphosis. Maximum first feeding occurred between 15.0 and 16.2 C. Larvae did not survive beyond first feeding when reared at mean temperatures of 5.1, 10.4, or 19.5 C and were unable to initiate feeding at mean rearing temperatures below 6.0 C. At a rearing temperature of 15.0 C in 16-L tanks, mean larval survival to 60 days post hatch (dph) was 14.1%. Mean overall length-specific growth rate for larvae reared to 60 dph at 15.0 C was 3.5%/d and mean absolute growth was 0.62 mm/d. Subsequent larval growth at 15.6 C began to taper off towards 70 dph at the onset of weaning which overlapped with larval metamorphosis. Growth plateaued at 85 dph, followed by a rebound between 90 and 95 dph. Survival was 100% when weaning onto a dry, pelleted diet was initiated at 70 dph with a 10-d live diet co-feeding period. These results are favorable and encourage the further pursuit of commercial witch flounder culture. [source]


An intensive hatchery rearing protocol for larvae of the bullseye puffer, Sphoeroides annulatus (Jenyns)

AQUACULTURE RESEARCH, Issue 10 2010
Maria Isabel Abdo-de la Parra
Abstract In this study bullseye puffer, Sphoeroides annulatus larvae were reared from hatching through to 1 or 2 months after weaning on an experimental scale in three replicate 600 L tanks and on three occasions during the spawning season (nine tanks in total). The rearing protocol used was green water (Nannochloropsis oculata and Isochrysis sp.) 100 000 cells mL,1 from 0 to 11 days after hatch (DAH), 5,10 rotifers, Brachionus rotundiformis mL,1 from 2 to 26 DAH, 0.1,1 Artemia mL,1 from 21 to 34 DAH and weaning from 29 to 34 DAH. Survival to a month after weaning was 1%, a total of 3153 juveniles were produced with an average wet weight of 0.29 ± 0.07 g and a length of 27.5 ± 0.82 mm. [source]


Effects of feeding frequency and feed type on the growth, feed utilization and body composition of juvenile olive flounder, Paralichthys olivaceus

AQUACULTURE RESEARCH, Issue 9 2010
Sang-Min Lee
Abstract A factorial (3 × 4) feeding trial was conducted to investigate the effects of feeding frequency and feed type on the growth performance, feed utilization and body proximate composition of juvenile olive flounder. Three feed types including a sinking moist pellet (MP), a sinking dry pellet (DP) and a floating extruded pellet (EP) were used. Fish (average weight, 11.1 ± 0.4 g) were randomly distributed in thirty-six 300 L tanks in a flowthrough system. Triplicate groups (30 fish per tank) of fish were fed each feed type to visual satiation at three meals per day, two meals per day, one meal per day and one meal every 2 days for 7 weeks. At the end of the feeding trial, the survival of fish was not significantly different among the treatments. Weight gain was affected by the feeding frequency. The highest weight gain was observed in fish fed the EP at three meals per day. The daily feed intake of fish fed the MP and DP tended to be higher than that of fish fed the EP at each feeding frequency. The feed efficiency and the protein efficiency ratio of fish fed the EP were higher than those of fish fed the MP and DP. The body proximate composition of fish was altered by the feeding frequency. The crude lipid content increased with the increase in the feeding frequency. The present findings suggest that three feedings per day at visual satiation of the floating EP may be sufficient for the maximal growth performance of olive flounder grown from 11 to 60 g. [source]


Apparent digestibility coefficients of four feed ingredients for Synechogobius hasta

AQUACULTURE RESEARCH, Issue 5 2009
Zhi Luo
Abstract Apparent digestibility coefficients (ADCs) of dry matter, crude protein, lipid, energy, phosphorus and amino acids in white fish meal, soybean meal, rapeseed meal and peanut meal were determined for Synechogobius hasta (28.65 ± 0.43 g, mean ± SD), using a reference diet with chromic oxide indicator and test diets that contained 70% reference diet, by weight, and 30% of feed ingredients. The juvenile S. hasta were held in 300 L tanks at a density of 30 fish per tank respectively. Faeces were collected from three replicate groups of fish by siphoning. The ADCs of dry matter and energy were the highest in white fish meal and the lowest in rapeseed meal (P<0.05). Crude protein ADC was the lowest in rapeseed meal (P<0.05) and showed no significant differences among other treatments (P>0.05). The highest phosphorus ADC was observed in white fish meal and differences were not marked for other treatments (P>0.05). Lipid ADC were above 90% and showed no significant differences among the treatments (P>0.05). Amino acid availability values for the test ingredients followed similar trend to values of protein digestibility. All amino acids were more available from fish meal than from plant protein ingredients. Among three plant meals, the availability of amino acids was higher in peanut meal and lower in rapeseed meal. [source]