• Journal of Welding and Joining
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• v.18 no.3
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• pp.83-88
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• 2000

Laser cladding processing allows rapid transfer of heat to the material being processed with minimum conduction into base metal, resulting in low total heat input. The effects of Nd:YAG laser cladding with wire feeding on the mechanical properties of Inconel alloy were investigated. inconel alloy is used as the material of nuclear steam generator tubing because of its mechanical properties and corrosion resistance properties. The device for Nd:YAG laser cladding with wire feeding was designed. It consists of the wire feeding system, the wire cladding system and the shielding gas system which prevents the clad layer from being oxidized. Experimental as results indicated that the wire feeding direction and position were important for laser cladding with wire feeding. The wire feeding speed should be adapted according to cladding speed for good shaping of clad layer. The effect of heat on the HAZ size can be limited and the growth of grain size of HAZ size was not serious. The hardness of clad layer and heat affected zone increased with increasing of cladding speed.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.967-974
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• 2012

Cultivation of Spirulina platensis using ammonium salts or wastewater containing ammonium as alternative nitrogen sources is considered as a commercial way to reduce the production cost. In this research, by analyzing the relationship between biomass production and ammonium-N consumption in the fed-batch culture of Spirulina platensis using ammonium bicarbonate as a nitrogen nutrient source, an online adaptive control strategy based on optical density (OD) measurements for controlling ammonium feeding was presented. The ammonium concentration was successfully controlled between the cell growth inhibitory and limiting concentrations using this OD-based feedback feeding method. As a result, the maximum biomass concentration (2.98 g/l), productivity (0.237 g/l d), nitrogen-to-cell conversion factor (7.32 gX/gN), and contents of protein (64.1%) and chlorophyll (13.4mg/g) obtained by using the OD-based feedback feeding method were higher than those using the constant and variable feeding methods. The OD-based feedback feeding method could be recognized as an applicable way to control ammonium feeding and a benefit for Spirulina platensis cultivations.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.487-489
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• 2000

An experiment was conducted for 56 days using nine castrated male Black Bengal goats (initial live weight 9.0 kg) aged about 5 months to study the effects of feeding Sesbania leaves as a sole feed on growth performance and nutrient utilization. The animals were fed ad libitum on either road-side grass, Sesbania aculeata leaves or Sesbania rostrata leaves. Average dry matter (DM) intake was 179, 229 and 259 g/d for goats fed road-side grass, Sesbania aculeata and Sesbania rostrata, respectively. Corresponding mean values for average daily live weight change were -6.6, 9.5 and 38.1 g, respectively. These values were higher (p<0.05) for goats fed Sesbania leaves than those given road-side grass. The apparent digestibility of all the proximate components except CF and the concentrations of DCP, TDN, DOM and ME of Sesbania leaves were higher (p<0.05) than those of road-side grass. Sesbania rostrata was superior (p<0.05) to Sesbania aculeata for nutrient digestibilities (except for NFE) and also for DOM, DCP and ME concentrations. Therefore, it may be concluded that the production of Sesbania rostrata, a legume fodder, should be encouraged for feeding goats.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.700-704
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• 2013

A study was conducted to investigate the effects of feeding medium chain triacylglycerol (MCT) on growth performance, plasma fatty acids, villus height and crypt depth in preweaning piglets. A total of 150 new born piglets were randomly assigned into one of three treatments: i) Control (no MCT); ii) MCT with milk (MCT+milk); iii) MCT without milk (MCT+fasting). Body weight, plasma fatty acid profiles, villus height and crypt depth were measured. Final BW for the Control and MCT+fasting was lower (p<0.05) than MCT+milk. The piglets fed with MCT regardless of milk provision or fasting had greater medium chain fatty acids (MCFA) than the Control. In contrast, the Control had greater long chain fatty acid (LCFA) and unsaturated fatty acid (USFA) than the MCT piglets. The piglets fed with MCT regardless of milk provision or fasting had higher villus height for the duodenum and jejunum after 6 h of feeding. Similar observations were found in piglets fed with MCT after 6 and 8 days of treatment. This study showed that feeding MCT to the piglets before weaning improved growth performance, with a greater concentration of MCT in blood plasma as energy source and a greater height of villus in duodenum, jejunum and ileum.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.43-46
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• 1971

1. The effects of different conditions of the feedings in connection with the bottom stata on the growth rate of Penaeus orientalis have been investigated. 2. The relationships between the days (D) after hatching and the carapace lengths (L) of p. orientalis are represented by the following equations: Feeding, muddy bottom: L=0.3939D+6.8965 feeding, sandy bottom: L=0.2652D+12.2620 Nonfeeding, sandy bottom: L=0.0713D+16.0655 Nonfeeding, muddy bottom: L=0.2852D+7.8620 3. The growth rate of the carapace length of p. orientalis in the region of muddy bottom is higher than that of the carapace in the sandy bottom whether the prawns are fed or not.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.36-40
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• 1989

The eels, Anguilla japonica, were reared in a tank with daily feeding for up to 97 days, and otoliths were regularly collected for the observation of their microstructures. Microscopic observation of the thin-sectioned otolith under dark field provided significant information on daily growth increments as well as the difference in visual contrast shown by the increments. Clearly defined elver mark formed during the metamorphosis from leptocephalus to the elver can be considered as the origin of the age for the sedentary yellow eel in continental water. The close correspondence between the number of increments outside elver mark and chronological age in days from the beginning of feeding indicates that increment deposition on a daily basis was initiated with the start of feeding for the sedentary yellow eel. Either 7 or 14 daily growth increments were grouped together into 2 alternative units, each distinguished by prominent checks or by visual contrast. The absence of any apparent environmental variations with 7 or 14 day period in the reared tank implies that the phase of the moon could be a zeitgeber for the endogenous rhythm.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.475-479
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• 1992

The non-steroidal ecdysone agonist RH 5849 showed almost similar LC.o values( 18.1-26.5 ppm) at all stages of larval development of the tobacco cutworm, Spodoptera litura, when treated by a leaf-disk dipping method. The feeding-inhibition rate for the 4th instar larvae was dose-dependent, and simultaneously the weight gain of 3rd instar larvae ceased within 48 hour after feeding of the cabbage leafdisk dipped into RH 5849 4.2 ppm solution. The systemic larvicidal effect of RH 5849 was compared at cabbage and tobacco whole plant test. The $LC_{50}$ values below 20 ppm(mg/kg soil) was lasted for 15 days in cabbage, 30 days in tobacco respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.4
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• pp.659-664
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• 1992

Twelve day old Pabna zebu calves of similar weights were assigned at random to 3 different calf starter-rations namely $T_0$, $T_1$ and $T_2$ to determine the effect of feeding regimes and growth pattern of calves upto 3 months of age. Calves allowed to intake starter 0.5 percent of body weight from 2nd week on to 7th weeks of age, while starter at 1 percent of body weight was allowed later on upto 13th weeks of age. Calves started to intake green grass after 2nd to 3rd weeks and average intake per day was limited to 1 kg upto the end of experiment, while calves started to take rice straw ad libitum after 6th weeks of age. Colostrum feeding was offered ad libitum and in addition calves suckled their dam's milk shortly before and after milking usually in the morning and evening. Growth of calves in different treatment groups was found statistically insignificant. The mean growth rate per head per day ranged from 196.43-375.0 g for $T_0$ group, 185.72-360.72 g for $T_1$ group and 180.1-385.72 g for $T_2$ group respectively between 1st to 7th weeks of age while the growth rate ranged from 309.53-328.57 g for $T_0$, 304.29-342.86 g for $T_1$ and 304.77-333.30 g for $T_2$ groups respectively from 9th weeks on to the end of the experiment.

• Journal of fish pathology
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• v.28 no.1
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• pp.53-62
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• 2015

Here, we report the physiological changes and growth in disk abalone, Haliotis discus discus, in relation to dietary supplementation with citrus pomace (CP) 6%, Ecklonia cava residue (ECR) 6%, and CP + ECR (3% + 3%). The composition and nutrient content, survival rate and growth rate were measured 0, 4, 8 and 12 weeks after feeding the supplemented diets of CP and/or ECR. Moreover, the experiment of low salinity stress (25psu) for environmental resistance was examined for a period of 48 hours after feeding the supplemented diets for 12 weeks. The activities of superoxide dismutase (SOD), catalase (CAT), lysozymes, respiratory burst, and phenoloxidase were measured. The moisture content and crude protein condition of the body were increased with the addition of ECR only (P<0.05). We observed higher levels of survival in the experimental group compared with the control group. Moreover, the growth disk abalone that were fed a diet containing ECR was higher compared with the control group. However, the growth of abalone fed a diet containing CP was similar to the control group. With a rearing condition of low salinity stress, survival rate and lysozyme activity were increased in the ECR group compared with the control group. Dietary ECR reduced the level of CAT activity to approximately 30% of the control, however the level of CAT activity in the ECR group was similar to the start level of the previous stress. These results suggest that dietary ECR gives rise to an enhanced immunity in disk abalone, as a result of the decrease in CAT and lysozyme activity in particular. Accordingly, the growth and survival rate were increased by feeding an ECR-supplemented diet in the rearing of disk abalone, Haliotis discus discus.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.229-247
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• 2014

Seven feeding trials were conducted to determine the effects of feeding rate and frequency in the Korean rockfish Sebastes schlegeli at seven different water temperatures. Two feeding-rate experiments for 5-g Korean rockfish at $17^{\circ}C$ and $20^{\circ}C$; three feeding rate experiments for 16-g Korean rockfish at $16^{\circ}C$ and $24^{\circ}C$; and finally, two feeding frequency experiments for 93- and 100-g at $15^{\circ}C$ and $20^{\circ}C$ were conducted. Twenty fish averaging $5.5{\pm}0.2$ g ($mean{\pm}SD$) were randomly distributed into 18 indoor tanks containing 40-L seawater from a semi-recirculation system. Fish were fed a commercial diet for 4 weeks at water temperatures of $17^{\circ}C$ and $20^{\circ}C$. Two feeding trials were conducted to determine the optimum feeding frequency in growing Korean rockfish reared at temperatures of $15^{\circ}C$ and $19^{\circ}C$. Broken line regression analysis of weight gain (WG) indicated that the optimum feeding rates of 5-g growing Korean rockfish were 4.48% (BW/day; BW, body weight) at $17^{\circ}C$ and 4.83% (BW/day) at $20^{\circ}C$. Broken line regression analysis of WG showed optimum feeding rates of 16-g juvenile Korean rockfish of 3.41% (BW/day) at $16^{\circ}C$, 3.75% (BW/day) at $20^{\circ}C$, and 3.34% (BW/day) at $24^{\circ}C$. The biological performance, results, along with morphological indices and serological characteristics, suggest that a feeding frequency of 1 meal/day was optimal to improve WG in growing Korean rockfish grown from 93 to 133 g at a water temperature of $15^{\circ}C$, and 100 to 132 g at $19^{\circ}C$.