• 열처리공학회지
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• 제11권3호
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• pp.168-176
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• 1998

The mechanical properties of mechanically alloyed Al-4wt%Mg alloys dispersed with $MgAl_2O_4$ dispersoilds at room and elevated temperatures were investigated. The powders in steady state during mechanical alloying consisted of Mg-supersatu rated Al solid solution and $Al_4C_3$ which resulted from the reaction of Al with C in process control agent (methanol). The hot-extruded materials consisted of uniformly dispersed fine $MgAl_2O_4$, ${\gamma}-Al_2O_3$, $Al_2O_3$ and matrix with extremly fine substructure. Tensile specimens prepared from the extruded bars were tested at room temperature to $400^{\circ}C$ under different strain rates. The tensile strength of alloys at room temperature ranged from 500 to 594MPa. At elevated temperatures, the tensile strengths and elongations decreased with increasing temperature. Adding 3% $MgAl_2O_4$ to Al-4wt%Mg increased the tensile strength of 50MPa at rowan temperature and 20MPa at $400^{\circ}C$.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.148-152
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• 1999

필리핀산 바나나를 온도(18$^{\circ}C$, 21$^{\circ}C$, $25^{\circ}C$)별로 5일간 후숙하고 13$^{\circ}C$와 및 상온(13-2$0^{\circ}C$)에서 16일간 저장하며 품질 변화를 조사하였다. 후숙 직후 바나나의 색도와 당도는 18$^{\circ}C$와 21$^{\circ}C$ 후숙이 4.2-5.2와 18.7-18.8$^{\circ}$이었고 $25^{\circ}C$ 후숙이 각각 5.5와 20.1$^{\circ}$를 나타냈다. 저장온도 및 후숙 방법에 따른 중량의 변화는 큰 차이 없이 저장 10일경에 약 1%로 증가하였으며, 당도는 20$^{\circ}$ 내외에서 거의 변화가 없거나 약간 증가 후 감소하였으며, 색도는 초기 5부근에서 2-4일 만에 완전 노랑인 7의 상태로 되었고, 혹반점은 정상 및 저온 후숙품이 13$^{\circ}C$에서 4일, 상온에서 2일만에 발생되었다. 변질율은 저온 및 정상 후숙이 13$^{\circ}C$에서 저장 6일 후 2.1%, 상온에서는 4일 후 4.2%로 그 이후부터는 75-100%로 급격히 증가하였으며, 고온 후숙은 13$^{\circ}C$ 저장에서 저장 2일 상온저장에서는 저장 초기 이후부터 변질이 급격히 진전되었다.

• 한국가금학회지
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• 제24권2호
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• pp.59-66
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• 1997

Optimum drying conditions to utilize porcine blood from slaughter house for blood meals, and the effects of blood meals on growth in broiler chicks were investigated. Moisture and protein con-tents of slaughter porcine blood were 79.8 and 16.4%, respectively. The protein contents of the flash dried blood meals at 80˚C were not different from those of the spray dried blood meals at 160 and 190˚C, but higher by 17% relative to those of the spray dried blood meals at 80 and 120˚C. Results from protein analysis by SDS-polyacrylamide electrophoresis showed that flash dried blood meals at 80˚C and spray dried blood meals at 160˚C were better than spray dried blood meals at 80, 120 and 190˚C in terms of protein quality. In Feeding Trial I with broiler chicks, body weights of chicks fed 2, 4 and 6% flash dried blood meal diets at 80˚C were increased at 35 days by 5.6, 7.9 and 4.0%, respectively, compared to control group(P<0.05). In Feeding Trial II, body weights of chicks fed 4 and 6% flash dried blood meal diets at 80˚C were increased at 42 days by 4.9 and 5.3%, respectively, compared to control group(P<0.05). Feed conversion ratios of chicks fed diets 4 and 6% flash dried blood meal diets at 80˚C were significantly improved at 42 days by 7.0 and 3.7%, respectively, compared to that of control group(P<0.05). The optimum drying condition of slaughter porcine blood seemed to be the flash drying method at 80˚C

• KSBB Journal
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• 제27권4호
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• pp.251-256
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• 2012

In this study we investigated the effect of temperature on the two-stage fermentation of Makgeolli using uncooked germinated black rice. The fermentation processes were conducted at $15^{\circ}C$ for three weeks and $25^{\circ}C$ for 7 days. The pH of Makgeolli at $25^{\circ}C$ increased from pH3.0 to pH 4.2, which was consistent with that at $15^{\circ}C$. In contrast total acidity of Makgeolli at $15^{\circ}C$ was about half of that at $25^{\circ}C$ (0.36% and 0.59%, respectively). By the 7 days-fermentation at $25^{\circ}C$, 11% of alcohol was produced, whereas three weeks were required for the same alcohol production at $15^{\circ}C$. In the case of sugar contents, the amounts of total glucose-equivalent reducing sugars and glucose increased at the end of the fermentation at $25^{\circ}C$ up to 2.25 mg/mL and 3.4 mM, respectively, whereas those at $15^{\circ}C$ were maintained at very low levels (0.18 mg/mL and 0.1 mM, respectively). Such limited supplement of sugars at $15^{\circ}C$ seemed to affect metabolism of yeast, resulting in different composition of organic acid. At $25^{\circ}C$, citric acid that was 73.4 ppm at the initial fermentation was consumed completely, whereas 20 ppm of citiric acid was remained at $15^{\circ}C$. In addition, acetic acid and lactic acid in Makgealli at $15^{\circ}C$ were 53% and 14% of those at $25^{\circ}C$.

• 한국토양비료학회지
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• 제48권5호
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• pp.451-455
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• 2015

An excess application of N fertilizer causes physiological and morphological disorder known as ammonium ($NH_4{^+}$) toxicity in Chinese cabbage and it has been to be an issue for appropriate N fertilizer management. Hence, the pot experiment was conducted in order to evaluate the alleviating effect of the application of the easily decomposable carbohydrate on $NH_4{^+}$ toxicity in Chinese cabbage. Four levels of urea at 0, 160, 320, and $640kg\;N\;ha^{-1}$, represented as T1, T2, T3, and T4, respectively, were applied. In order to evaluate the alleviating effect of the application of the easily decomposable carbohydrate (sucrose) at T3 and T4 where $NH_4{^+}$ toxicity had occurred, five levels of sucrose were applied to meet C/N ratios of 0, 2, 4, 6, and 10, respectively. Our results showed that the $NH_4{^+}$ toxicity was observed at T3 and T4 at 5 days after treatment (DAT). $NH_4{^+}$ toxicity contributed to decrease fresh weight, length of leaves, length of root, and number of leaves significantly (p<0.05). The application of sucrose as a source of mitigating $NH_4{^+}$ toxicity had a good performance at T3 with the alleviating effect as 73 % and reduced in $NH_4{^+}-N$ content in soil at 29 DAT. In the maximum N rate of T4, however, sucrose application recovered it as 32 % only compared to T2 even though the same C/N ratio was treated. Consequently, sucrose as the easily decomposable carbohydrate played crucial role to reduce $NH_4{^+}$ concentration in soil and finally alleviated $NH_4{^+}$ toxicity in plant.

• The Korean Journal of Physiology
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• 제5권2호
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• pp.29-40
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• 1971

Oxygen consumption, pulmonary ventilation, heart rate, and breathing frequency were measured on 8 men walking on a treadmill carrying load of 9 kg on hand, back, or head. Besides measurements were made on subjects carrying loads of 2.6 kg each on both feet. The speed of level walking was 4, 5, and 5.5km/hr and a fixed speed off km/hr with grades of 0, 3, 6, and 9%. Comparisons were made between free walking without load and walking with various types of loads. The following results were obtained. 1. In level or uphill walking the changes in oxygen consumption, pulmonary ventilation, breathing frequency and heart rate were smallest in back load walking, and largest in hand load walking. The method of back load was most efficient and hand load was the least efficient. The energy cost in head load walking was smaller than that of in hand load walking. It was assumed that foot load costed more energy than hand load. 2. In level walking the measured parameters increased abruptly at the speed of 5.5 km/hr. Oxygen consumption in a free walking at 4 km/hr was 11.4ml/kg b.wt., and 13.1 ml/kg b.wt. 5.5 km/hr, and in a hand load walking at 4 km/hr was 13.9, and 18.8 ml/kg b. wt. at 5.5 km/hr. 3. In uphill walking oxygen consumption and other parameters increased abruptly at the grade of 6%. Oxygen consumption at 4 km/hr and 0% grade was 11.4 ml/kg b. wt., 13.6 at 6% grade, and 16.21/kg b. wt. at 9% grade in a free walking. In back load walking oxygen consumption at 4km/hr and 0% grade was 12.3 ml/kg b.wt.,14.9 at 6% grade, and 18.7 ml/kg b.wt. In hand load walking the oxygen consumption was the greatest, namely, 13.9 at 0% grade, 17.9 at 6%, and 20.0 ml/kg b. wt. at 9% grade. 4. Both in level and uphill walking the changes in pulmonary ventilation and heart rate paralleled with oxygen consumption. 5. The changes in heart rate and breathing frequency in hand load were characteristic. Both in level and uphill walk breathing frequency increased to 30 per minute when a load was held on hand and showed a small increase as the exercise became severe. In the other method of load carrying the Peak value of breathing frequency was less than 30 Per minute. Heart rate showed 106 beats/minute even at a speed of 4 km/hr when a load was held on hand, whereas, heart rate was between, 53 and 100 beats/minute in the other types of load carriage. 6. Number of strides per minute in level walking increased as the speed increased. At the speed floater than 5 km/hr number of strides per minute of load carrying walk was greater than that of free walking. In uphill walk number of strides per minute decreased as the grade increased. Number of strides in hand load walk was greatest and back load walk showed the same number of strides as the free walk.

• 수산해양기술연구
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• 제33권2호
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• pp.118-131
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• 1997

본 연구에서는 권현망의 축소, 개량을 전제로 현행 어구를 2/1로 축소하여 해상실험을 행하였다. 실험에서는 양선간격을 100m, 200m, 300m의 3단계로, 예망속도를 0.6k't. 0.9k't, 1.2k't의 3단계로, 변화시켜가며 오비기, 수비, 자루그물, 깔대기 등의 망고를 계측하여 어구의 전개성능을 파악하였으며, 끌줄의 예망장력도 계측하여 어구어법의 개선방향을 제시하였다. 본 연구의 결과를 요약하면 다음과 같다. 1. 예망중 권현망의 날개에서의 망고는 수비에서 순조시 12.0~8.7m, 역조시 10.0~7.0m로 오비기에서 순조시 19.8~8.4m, 역조시 16.3~4.9m로 나타났다. 이들 망고는 예망속도와 양선간격의 증가에 따라 점차 낮아지며, 오비기와 수비에서 각각 정상적인 전개의 16%~66%, 18%~32% 정도를 나타내었다. 2. 자루에서의 망고는 입구에서 순조시 12.8~7.9m, 역조시 9.7~7.4m로, 깔대기에서 순조시 5.1~3.4m, 역조시 5.1~4.4m로 나타났으며, 입구에서의 망고는 정상적인 전개의 57%~98% 정도로 전개되었다. 이때 깔대기 망형상은 원형에 가까우나 예망속도가 저속일 때에 위쪽으로 떠오르는 경향을 보였다. 3. 자루의 형상은 자루뒤끝의 망고가 순조시 9.3~7.1m, 역조시 8.8~7.4m로 나타났으며, 전체적으로 자루뒤끝이 크게 끌어 올려지는 현상이 나타났으나, 이 현상은 예망속도가 느릴수록 양선간격이 좁을수록 더 두드러졌다. 4. 예망장력은 순조시 648~2,716kg, 역조시 1,050~6,010kg으로 나타났으며, 예망속도가 예망장력에 가장 큰 영향을 주는 것으로 나타났다. 5. 어구의 예망수층은 예망속도 및 양선간격이 증가할수록 안정되며, 예망속도가 느리고 양선간격이 좁을수록 불안정하여 자루뒤끝이 들리는 현상을 나타내었다.

• Journal of Magnetics
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• 제19권1호
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• pp.5-9
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• 2014

The amine functionalized $CoFe_2O_4$ nanoparticles were prepared by thermal decomposition method at reflux temperatures $160^{\circ}C$ and $172^{\circ}C$. The obtained $CoFe_2O_4$ nanoparticles at $160^{\circ}C$ reflux temperature show aggregation free poly-dispersed nanoparticles in 4-15 nm range. In an elevated reflux temperature of $172^{\circ}C$, $CoFe_2O_4$ show aggregated poly-dispersed nanoparticles in the size range of 20-46 nm. The saturation magnetization value at 300 K exhibited 51 emu/g at reflux temperature of $160^{\circ}C$. However, the sample synthesized at an elevated temperature of $172^{\circ}C$ has shown a coercive field value of 560 Oe with saturation magnetization of 68 emu/g.

• Asian-Australasian Journal of Animal Sciences
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• 제8권6호
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• pp.563-566
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• 1995

To improve the nutritive value of wheat straw it as treated with 0, 3, 4 and 5 percent levels of urea, 0 and 4 percent level of alkali at 40, 50 and 60 percent moisture levels and stored at room temperature. Total nitrogen contents of the straw increased significantly, from 0.77 percent with no urea treatment to 0.87, 1.16 and 1.19 percent with 3, 4 and 5 percent urea levels, respectively. Percent retention of nitrogen was 63.73 percent. Alkali treatment at 4 percent level, lowered significantly the crude fibre contents of the straw from 41.86 percent in control to 40.21 percent in the treated straw. Moisture level of 40 percent significantly lowered (p < 0.05) the crude fibre contents. Total ash content of straw increased significantly by urea and alkali treatment. Alkali treatment improved significantly the sodium contents also. The results of the study indicated that most beneficial results were obtained with 4 percent urea, 4 percent alkali at 50 percent moisture level.

• 대한핵의학회지
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• 제14권1호
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• pp.1-8
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• 1980

Serum TSH levels were measured by radioimmunoassay before and after intravenous administration of synthetic thyrotropin-releasing hormone (TRH) to 15 normal subjects and 55 patients with primary thyroid disease (14 patients with euthyroidism, 24 patients with thyrotoxicosis and 17 patients with hypothyroidism) to evaluate pituitary TSH reserve and its diagnostic availability. The observed results were as follows. 1. In normal subjects, serum TSH responses to synthetic TRH were $3.2{\pm}1.0$ at 0min (baseline TSH level), $8.0{\pm}4.0$ at 10min, $11.7{\pm}5.0$ at 20min, $13.7{\pm}7.1$ at 30min, $9.7{\pm}5.0$ at 60min., $5.2{\pm}2.0$ at 120min. and $3.6{\pm}0.4{\mu}U/ml$ at 180 min. Serum TSH peaked at $20{\sim}30$ minutes and returned nearly to baseline at 180minutes. 2. In euthyroid group, serum TSH responses to synthetic TRH were $3.3{\pm}1.6$ at 0min, $8.6{\pm}8.0$ at 10min, $10.9{\pm}8.5$ at 20min, $12.5{\pm}8.4$ at 30min, $9.0{\pm}5.9$ at 60min, $5.6{\pm}2.6$ at 120min and $3.5{\pm}1.3{\mu}U/ml$ at 180min. No significant difference revealed between euthyroid group and normal subjects (p>0.05). 3. In hyperthyroid group, serum TSH responses to synthetic TRH were $1.5{\pm}0.6$ at 0min, $2.2{\pm}0.8$ at 10min., $2.3{\pm}1.0$ at 20min., $2.4{\pm}1.5$ at 30min., $2.1{\pm}1.1$ at 60min., $1.9{\pm}0.2$ at 120min. and $1.5{\pm}0.8{\mu}U/ml$ at 180min., No response to TRH showed. 4. In hypothyroid group, mean values of serum TSH response to synthetic TRH were 42.0 at 0min., 60.6 at 10min., 124.8 at 20min., 123.0 at 30min., 101.6 at 60min., 64.3 at 120min. and $15.5{\mu}U/ml$ at 180 min., Patients with primary hypothyroidism showed an exaggerated TSH response to synthetic TRH despite their high basal TSH. 5. Side effects attending synthetic TRH administration were transient nausea (59.0%), desire to micturate (59.0%), feeling of flushing(19.7%), dizziness (45.9%), metallic taste (9.8%) and headache (19.7%). Any side effect didn't show in 16.4%. These symptoms began almost immediately after TRH intravenous injection and lasted several minutes, and not related to dose or response in the person experiencing it.