• 한국수산과학회지
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• 제27권1호
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• pp.69-82
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• 1994

해조류를 첨가한 사료가 조피볼락의 어린 시기에 미치는 생리적 효과를 알아보기 위하여, 전장 $2.99{\pm}0.23\;cm$, 체중 $1.03{\pm}0.18\;g$의 인공종묘에게 미역분말을 각각 $3\%,\;5\%,\;7\%$ 첨가한 사료와 비첨가 사료를 주면서 140일간 사육하여 전장$18.52{\pm}1.07\;cm$, 체중 $120.64{\pm}19.32\;g$이 될 때까지의 어체 성장, 생존율, 체조성, 혈액조성을 서로 비교하고, 저산소 및 기아 내성에 관한 생리활성을 연구하였다. 1. 전장과 체중의 성장은 $5\%$의 미역 첨가시 가장 좋았으며, $3\%,\;7\%$, 대조구인 $0\%$ 순이었다. 2. 실험구별 사료효율은 $3\%,\;5\%,\;7\%,\;0\%$구의 순으로 높았으며, 생존율은 $7\%,\;5\%,\;3\%,\;0\%$구 순이었다. 3. 사육종료시의 체조성에 있어 등 근육의 수분, 조단백질, 조지방 및 조회분은 실험구별로 큰 차이를 보이지 않았으나, 전내장의 조지방 함량은 미역 첨가구가 대조구에 비해 많았다. 4. 미역 첨가구는 $0\%$구 보다 헤마토크릿트값이 크고, 평균적혈구수도 많았다. 5. 실험종료시 사료별 어체의 저산소내성은 미역 첨가구가 대조구에 비해 강했다. 6. 사육실험 종료후 31일간의 기아 실험에서 미역 첨가구의 어체중은 대조구에 비해 적게 감소하였다. 7. 조피볼락 양식에서 사료에 미역을 첨가해 줄 경우, 그 비율은 $5\%$가 가장 적합하며 어체의 생리조건에 좋은 영향을 줄 수 있는 것으로 판단되었다.

• 한국수산과학회지
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• 제53권4호
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• pp.597-605
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• 2020

The diatom Melosira nummuloides is a microalga that is widely distributed in freshwater and seawater is used is used in the production of silicon and fucoxanthin. The objective of this experimental study was to determine the effects of diatom powder on the physiology of olive flounder Paralichthys olivaceus. In four feeding groups consuming 0%, 1%, 2% and 3% diatom powder. After 8 weeks of feeding, we investigated P. olivaceus growth rate, feed efficiency rate, survival rate, anti-oxidant enzyme rate, non-specific immune activity and immune gene expression. The rates of growth rate, feed efficiency rate and survival were significantly higher for olive flounder in all diatom groups than in the control. The results for anti-oxidant enzyme, superoxide dismutase and catalase showed no significance, but glutathione was significant, depending on the concentration of diatom addition. The galectin and lysozymes of immune genes were increased in the control group. Galectin and lysozymes were thought to have increased due to infections by from pathogens during the experiment period. These results suggest that the addition of diatoms to olive flounder diets is effective in enhancing growth rate and innate immunity.

• Journal of Welding and Joining
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• 제25권1호
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• pp.30-36
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• 2007

A joining of dissimilar metal combination faces significant problems such as poor strength and cracking associated with brittle intermetallic compounds(IMC) formed. An application of laser allows low heat input; leading to less dilution and smaller heat affected zone. The $CO_2$ laser overlay was conducted on an AC2B alloy with feeding Fe-based powders. The overlay area was significantly influenced from the travel velocity rather than the powder feeding rate. The interface between the overlay and substrate consisted of the hard and brittle IMC($FeAl_3,\;Fe_3Al,\;Fe_2Al_5$), which initiating and propagating the crack. The reciprocating test for the slide wear was conducted on a multi-pass overlay experiment. Comparing with the multi-pass overlay with no overlap, the overlay with 50% overlap showed better wear resistance.

• 한국환경과학회지
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• 제31권5호
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• pp.457-460
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• 2022

This study was conducted to investigate the effects of dietary supplementation with Ptecticus tenebrifer powder on the mortality and meat quality of Korean native chickens. A total of 40,000 Korean native chickens (1 day old, Hanhyup No. 3) were allocated to two dietary treatments (20,000 chickens in each treatment), which were fed the following: basal diet (control) and 1% of Ptecticus tenebrifer powder (T1). Feeding trials were conducted for 12 weeks, and mortality was measured weekly. At the end of the experimental period, 16 chickens (8 chickens in each treatment) were selected and slaughtered to obtain breast meat. The items used to analyze meat quality were pH, TBARS, and meat color. The weekly mortality rate was decreased by around 2 to 3 times in the T1 treatment group compared with the control group. The pH, TBARS, L^*, and b^* values of Korean native chicken breast were not affected by Ptecticus tenebrifer powder supplementation (p>0.05); however, a^* values showed statistical significance (p<0.05). In conclusion, the addition of 1% Ptecticus tenebrifer powder reduced mortality rate and demonstrated its potential in livestock environmental management.

• 한국분말재료학회지
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• 제19권5호
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• pp.356-361
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• 2012

The ultra-fine and less agglomerated titanium carbonitride particles were successfully synthesized by magnesiothermic reduction with low feeding rate of $TiCl_4+1/4C_2Cl_4$ solution. The sub-stoichiometric titanium carbide ($TiC_{0.5{\sim}0.6}$) particles were produced by reduction of chlorine component by liquid magnesium at $800^{\circ}C$ of gaseous $TiCl_4+1/4C_2Cl_4$ and the heat treatments in vacuum were performed for 5 hours to remove the residual magnesium and magnesium chloride mixed with produced $TiC_{{\sim}0.5}$. The final $TiC_{{\sim}0.5}N_{0{\sim}0.5}$ particle with near 100 nm in mean size and high specific surface area of $65m^2/g$ was obtained by nitrification under nitrogen gas at $1,150^{\circ}C$ for 2 hrs.

• 한국세라믹학회지
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• 제36권7호
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• pp.742-750
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• 1999

화학기상응축법을 이용한 TiO2 나노분말합성시 전구체 주입속도 및 산소 반응기체유량의 변화에 따른 나노입자의 형성과정을 분말특성의 관점에서 조사하였다. 기상합성반응의 주요 열역학, 동역학적 인자인 과포화도, 충돌율, 체류시간의 상기 두 공정변수에 대한 의존성을 이론적으로 평가하였고, 이를 0.376, 0.742 m//min의 두 전구체 주입속도 조건에서 산소유량을 1에서 2slm까지 변화시키며 합성한 TiO2 나노분말의 특성과 관련하여 분석하였다 모든 조건에서 합성된 TiO2 분말은 20~30 nm의 크기를 갖는 미세한 anatase 상과 극소량의 rutilc상이 혼합되어 서로 느슨한 결합을 하고 있었다 전구체 주입속도가 0.376m//min의 경우, 전반적인 입도와 응집도는 0.742 m//min에 비해 작았으며, 산소유량이 증가할수록 체류시간과 충돌율이 감소하여 형성된 TiO2 분말의 입도는 감소하였다. 또한 산소유량 증가에 따른 과포화도의 감소는 분말형성과정과 기구에 영향을 미치는 것으로 판단되나, 정확한 분석을 위해서는 각각의 독립적인 열역학 및 동역학적 변수 조건하에서의 면밀한 고찰이 요구되었다.

• 한국수산과학회지
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• 제45권6호
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• pp.679-685
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• 2012

A study was carried out to observe the effects of feed types on the growth, feed preference, and enteric feed transition rate of juvenile starry flounder, Platichthys stellatus for 45 days. Fifty fish (avg. 135 g) were stocked each in replication, and fed a commercial extruded pellet diet (EP, 45% protein) and a moist pellet diet (MP, 65% raw mackerel+35% feed powder in wet basis), respectively. The MP presented the higher performance than that of the EP on the feed efficiency ($68.3{\pm}0.9%$ for EP and $92.3{\pm}4.3%$ for MP) and the specific growth rate ($1.07{\pm}0.07$ for the EP and $1.20{\pm}0.05%$ for the MP). In contrast, the EP showed the higher feed preference in terms of the daily feed intake ($1.57{\pm}0.08%$ for the EP and $1.30{\pm}0.01$ for the MP) and the ad libitum feeding rate after a fast of 72 hours (1.73% for the EP and 1.35% for the MP). The feed transition rate through intestinal canals decreased exponentially in both the EP and the MP, showing the faster transition rate with the EP. In the result, starry flounder appeared to have the better feed preference to the EP, but have the higher feed efficiency and growth performance to the MP.

• Journal of Ginseng Research
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• 제4권2호
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• pp.146-164
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• 1980

In this paper it was attempted to observe the effect of defatted panax ginseng supplement of the growth rate, feed and protein efficiency ratios, and the contents of cholesterol, total lipid and protein in the serum, liver and aorta in Sprague-Dowley Albino male rat (weighing 83 ${\pm}$ 4 g). Seven kinds of experimental diets were prepared as follows : Stock (control) diet, ginseng control diets supplemented with 0.5, 1.0 and 3.0% of ginseng powder to the stock diet, and defatted ginseng Powder diets supplemented with 0.5, 1.0 and 3.0% of defatted ginseng powder to the stock diet. .All diets contained same level of lipid and protein, respectively. The results obtained are as follows : 1. The growth rate in the feeding group of 0.5% defatted ginseng powder diet for 16week were higher than other diet groups. 2. Feed and Protein efficiency in 0.5% defatted ginseng group showed similar tendency to that in body growth rate. 3. The total cholesterol contents in the serum of 0.5% defatted ginseng Powder diet$.$ group showed the tendency to decrease gradually for 4 to 12 weeks, maintaining higher level than other groups. The free cholesterol contents in the serum of defatted ginseng powder diet group in 8 the and 16th weeks were higher than all ginseng control diet group. The total and free cholesterol contents in the liver of all defatted ginseng diet groups in 16th week were higher than hose of all ginseng control groups. The total cholesterol content at 12h week and the free cholesterol content at 16th week i n the aorta of all defatted ginseng diet groups were lower than those of ginseng control groups, respectively. 4. The total lipid contents in the serum of 1.0 and 3.0% defatted ginseng diet groups at 2nd to I2th weeks were lower than other groups, and those in the liver and aorta of all defatted ginseng diet groups at 12th weeks were lower than those of ginseng control diet groups. 5. The protein contents of the serum and aorta were continuously increased throughout whole experimental period in all experimental groups. The protein content of the liver of all groups were decreased at 2nd week and after then no change was observed.

• 한국분말재료학회지
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• 제15권3호
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• pp.221-226
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• 2008

Silver coated copper composite powders were prepared by electroless plating method by controlling the activation and deposition process variables such as feeding rate of silver ions solution, concentration of reductant and molar ratio of activation solution $(NH_4OH/(NH_4)_2SO_4)$ at room temperature. The characteristics of the product were verified by using a scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption (A.A.). It is noted that completely cleansing the copper oxide layers and protecting the copper particles surface from hydrolysis were important to obtain high quality Ag-Cu composite powders. The optimum conditions of Ag-Cu composite powder synthesis were $NH_4OH/(NH_4)_2SO_4$ molar ratio 4, concentration of reductant 15g/l and feeding rate of silver ions solution 2 ml/min.

• Journal of Animal Science and Technology
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• 제66권1호
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• pp.103-114
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• 2024

This study was done to investigate the effects of the incorporation of Achyranthes japonica extracts (AJE) in diet on the production parameters of growing pigs. Exp 1: Total, 105 crossbred pigs (average body weight: 24.47 ± 2.46 kg) were used in a 6-week feeding trial. Pigs (seven replicates, five pigs per pen) were allotted randomly to three treatments. Dietary treatments: CON (basal diet); basal diet with 0.025% AJE, and basal diet + 0.050% AJE). Growth performance, nutrient digestibility, fecal microbial count, and fecal noxious gas were assessed in this study. Average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F) were not affected by the addition of up to 0.05% AJE. In the case of apparent total tract digestibility (ATTD), dry matter (DM), nitrogen (N), and digestible energy (DE) were not changed in 3rd and 6th weeks of the feeding trial through the addition of AJE up to 0.05% in the growing pig diet. In microbial count, Lactobacillus and Escherichia coli count at 3rd and 6th week was similar in all the treatment diets. The inclusion of AJE at levels up to 0.05% in growing pig diet had no effect on the production of NH3, H2S, acetic acid, and CO₂ in the feces. After ending the Exp 1, a total of nine pigs were divided into three treatment groups. Treatment diets were included, TRT1, basal diet + powder quercetin 30 g; TRT2, basal diet + powder quercetin 150 g; TRT3, basal diet + powder quercetin 300g. Rate of absorption in blood was increased with the higher dose of quercetin. The results suggested incorporation of AJE up to 0.05% has no significant effect on ADG, ADFI, and G:F, as well as DM, N, and DE digestibility, fecal microbial count, and fecal noxious gas emission in growing pigs, even though no negative effect was found.