• Archives of Pharmacal Research
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• 제22권2호
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• pp.165-172
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• 1999

In the present work , the transport mechanism of a capsaicin derivative, DA-5018, through blood-brain barrier (BBB) has been investigated to evaluate the feasibility of potential drug development. The result of pharmacokinetic parameters obtained from the intravenous injection of plasma volume marker,$[3^H]RSA$ and $[{14}^C]DA-5018$, indicated that both AUC, area under the plasma concentration curve and VD, volume of distribution in brain of $[3^H]RSA$ agreed with those reported ($1620{\pm}10 $percentage injected dose minute per milliliter (%IDmin/ml) and $12.0{\pm}0.1{\mu}l/g$, respectively). Elimination half-life and AUC of $[{14}^C]DA-5018$is corrected by the PHLC analysis, 19.6$\pm$1.2 min and 7.69$\pm$0.85% IDmin/ml, respectively. The metabolic rate of $[{14}^C]DA-5018$was very rapid. The blood-brain barrier permeability surface area (PS) product of $[{14}^C]DA-5018$ was calculated to be 0.24$\pm$0.05 $\mu$l/min/g. The result of internal carotid artery perfusion and capillary depletion suggested that [14C]DA-5018 pass through BBB with the time increasingly. Investigation of transport mechanism of $[{14}^C]DA-5018$ using agonist and antagonist suggested that vanilloid (capsaicin) receptor did not exist in the BBB, and nutrient carrier system in the BBB has no effect on the transport of DA-5018. In conclusion, despite the fact that penetration of DA-5018 through BBB is significant, the intact drug found in the brain tissue is small because of a rapid metabolism. Therefore, for the central analgesic effect of DA-5018, the method to increase the metabolic stability in plasma and the brain permeability should be considered.

• Journal of Forest and Environmental Science
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• 제34권4호
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• pp.284-292
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• 2018

The study investigated the concentrations of Pb in soil, air and fruit of C. sinensis in selected landuse types in Port Harcourt Metropolis, Rivers State, Nigeria. Five fruits of C. sinensis were collected randomly in residential, commercial, industrial and natural forest (control). The weight, length and width of the C. sinensis fruits were measured. A total of three soil samples were collected around the C. sinensis trees where the fruits were collected into well labeled polythene bags and thereafter taken to laboratory for analysis. Pb concentrations in C. sinensis and soil samples were analysed using atomic absorption spectrophotometer (AAS). The concentration of Pb in the air was measured for 14 days using Aeroquel 500. The significant relationship between Pb concentration in the C. sinensis fruits, soil and air was determined using Spearman's rank correlation. Findings showed that the mean weight and width of C. sinensis fruits were highest in the residential landuse while the mean length of C. sinensis fruits was highest in the industrial landuse. However, the mean Pb concentration in the C. sinensis fruit was highest in the industrial landuse ($0.46{\pm}0.15mg\;kg^{-1}$), commercial landuse ($0.33{\pm}0.09mg\;kg^{-1}$) and the least was found in the natural forest ($0.25{\pm}0.06mg\;kg^{-1}$). The mean Pb concentration in the soil was highest in the industrial landuse ($0.177{\pm}0.16mg\;kg^{-1}$) and commercial landuse ($0.121{\pm}0.10mg\;kg^{-1}$). However, the mean Pb concentration in the air was highest in the industrial landuse ($0.85{\pm}0.09mg\;kg^{-1}$) and followed by commercial landuse ($0.30{\pm}0.17mg\;kg^{-1}$). The correlations between the Pb concentration in the C. sinensis fruit and soil (r=0.768, p<0.05) and air (r=0.642, p<0.05) were significant. The study concluded that the Pb concentration in the C. sinensis fruits was higher than the WHO standard; hence people should be discouraged to consume them, especially those from the industrial and commercial areas.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권4호
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• pp.259-273
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• 2021

We conducted a study to investigate the characteristics of the carbon cycle of two streams (located in Shig a Prefecture, Japan), having similar size, namely, the Adokawa stream (length: 52 km, area: 305 km², watershed population: 8,000) and the Yasukawa stream (length: 62 km, area: 380 km², watershed population: 120,000), but with different degree of human activity. Samples were collected from these two streams at 14 (Adokawa stream) and 23 (Yasukawa stream) stations in the flowing direction. The dissolved inorganic carbon (DIC) concentration and the stable carbon isotope ratio of DIC (δ¹³C-DIC) were measured in addition to the watershed features and the chemical variables of the stream water. The δ¹³C-DIC (-9.50 ± 2.54‰), DIC concentration (249 ± 76 µM), and electric conductivity (52 ± 13 µS/cm) in Adokawa stream showed small variations from upstream to downstream. However, the δ¹³C-DIC (-8.68 ± 2.3‰) upstream of Yasukawa stream was similar to that of Adokawa stream and decreased downstream (-12.13 ± 0.43‰). DIC concentration (upstream: 272 ± 89 µM, downstream: 690 ± 37 µM) and electric conductivity (upstream: 69 ± 17 µS/cm, downstream: 193 ± 37 µS/cm) were higher downstream than upstream of Yasukawa stream. The DIC concentration of Yasukawa stream was significantly correlated with watershed environmental variables, such as, watershed population density (r = 0.8581, p<0.0001, n = 23), and forest area percentage of the watershed (r = -0.9188, p<0.0001, n = 23). δ¹³C-DIC showed significant negative correlation with the DIC concentration (r = -0.7734, p<0.0001, n = 23), electric conductivity (r = -0.5396, p = 0.0079, n = 23), and watershed population density (r = -0.6836, p = 0.0003, n = 23). Our approach using a stable carbon isotope ratio suggests that DIC concentration and δ¹³C-DIC could be used as indicators for monitoring the health of stream ecosystems with different watershed characteristics.

• Korean Chemical Engineering Research
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• 제48권2호
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• pp.253-258
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• 2010

암모니아수를 이용한 이산화탄소 흡수분리공정에서 흡수액의 재생조건(온도, 압력)이 이산화탄소 흡수성능에 미치는 영향을 조사하였다. 실험에 사용된 흡수액은 탄산암모늄($(NH_4)_2CO_3$)을 물에 용해시키어 $CO_2$ 로딩($mol\;CO_2/mol\;NH_3$)이 0.5, 용액 내의 암모니아수 농도가 14, 20, 26 및 32 wt%로 되도록 제조하였고, 이산화탄소의 흡수에 앞서 재생압력(6~18 bar)을 조절하면서 $120{\sim}160^{\circ}C$의 온도범위로 제조된 흡수액을 가열하여 재생하였다. 재생된 흡수액을 기포 반응기에 넣고 12 vol%의 $CO_2$를 함유한 기체를 주입하여 흡수반응을 수행하였다. 실험결과 26 wt%의 암모니아수가 대체적으로 $CO_2$ 흡수량이 높았으며, 특히 재생온도가 $150^{\circ}C$, 재생압력이 14 bar일 때의 $CO_2$ 흡수량은 본 연구의 실험조건에서 $45ml\;CO_2/g$ solution으로 가장 높은 값을 보였다. 적정을 통해 재생된 용액을 분석한 결과 재생압력이 높아질수록 암모니아 손실량은 감소하고, 재생온도가 높아질수록 암모니아 손실량이 증가하였다. 또한 암모니아 농도증가에 따라 암모니아 손실량이 비례적으로 증가하였다. Electrolyte NRTL 모델을 사용하여 Aspen Plus에 적용한 결과 실험 데이터와 거의 일치함을 보였다.

• 공업화학
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• 제30권1호
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• pp.17-22
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• 2019

본 연구에서는 소수성 사슬의 길이를 증가시키고 1,4-부탄디올을 스페이서로 사용하여 양이온성 제미니형 계면활성제를 합성하였으며 $^1H-NMR$로 확인하였다. 합성한 계면활성제의 외형은 백색 분말로 나타났으며, Kraffts 점은 $0^{\circ}C$ 이하로 나타났다. 측정된 임계미셀농도(c.m.c)는 표면장력법에 의해 $1.8{\times}10^{-3}{\sim}6.5{\times}10^{-4}mol/L$이었고 표면 장력은 22.5~26.1 dyne/cm이었다. Ross-Miles 방법에 의한 CG 14-6E-14의 초기 거품 높이는 16 cm이었고 5 min 후 높이 14 cm를 나타내어, 가장 좋은 초기 기포력과 기포안정성을 갖는 것을 확인하였다. 또한, 합성한 양이온 제미니 계면활성제와 일반적으로 사용하고 있는 cetyltrimethylammonium bromide (CTAB)의 기포력 및 유화안정성을 비교하였다.

• Elastomers and Composites
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• 제14권4호
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• pp.231-252
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• 1979

Polymerization of 2-pyrrolidone was carried out through anionic mechanism using $SO_2/KOH$ as catalyst. The effects of KOH concentration, $SO_2/KOH$ mole ratio and temperature on polymerization were investigated. The conversion and viscosity of polymers were measured at various polymerization conditions. It was observed that as the concentration of KOH was increased, equilibrium conversion was also increased. It was, however, found that after the concentration of KOH was reached above 8 mole percent, the equilibrium conversion was decreased. The highest rate of polymerization and maximum conversion were obtained when $SO_2/KOH$ mole ratio was around 0.5. It was also found that the rate of polymerization and the equilibrium conversion were higher at $50^{\circ}C$. than at $30^{\circ}C$. but the viscosity of polymer solution at $50^{\circ}C$. was not so high as expected. The rate constant, $K_p$ of polymerization, was determined by least square method: the value of $K_p$ was observed as 16 liter/mole hour at $50^{\circ}C$. and 2.6 liter/mole hour at $30^{\circ}C$., respectively. The mechanism of polymerization was also discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제17권12호
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• pp.1663-1668
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• 2004

This study was carried out to evaluate the potential nutritive value of commonly found grasses collected at native pasture in West Sumatra, Indonesia during dry and rainy seasons. Variables measured included chemical composition, in vitro digestibility, concentration of Ca, P and Mg, gas production and metabolizable energy (ME) content of the grasses. The results showed that species and season had significant effect on chemical composition and mineral concentration. Crude protein content in the dry season ranged from 6.5% (B. decumbens) to 14.4% (P. maximum) and increased slightly from 7.8% (B. decumbens) to 14. 8% (A. compressus) in the rainy season. Data on fiber fraction showed that grass contained more NDF, ADF and ADL in dry season than in rainy season. Data on mineral concentration showed that C. plectostachyus and P. maximum in dry season had higher Ca than those of other species, while in rainy season P. maximum had highest Ca concentration. In dry season, the DMD varied from 50. 4% (P.purpuphoides) to 59.1% (P. purpureum), while in rainy season ranged from 50.3% (A. gayanus) to 61.8% (P. purpureum). The potential and rate of gas production were significantly (p<0.05) affected by species and season. During dry season, potential of gas production ranged from 21.8 ml/200 mg (A. compressus) to 45.1 ml/200 mg (C. plectostachyus), while in rainy season it varied from 35.6 ml/200 mg (A. gayanus) to 47.5 ml/200 mg (P. purpureum). ME content of grasses varied from 6.0 to 8.3 MJ/kg in dry season and increased slightly from 6.4 to 8.6 MJ/kg in rainy season. Both in dry and rainy seasons, the highest ME content was occurred in P. purpureum and C. plectostachyus. In conclusion, nutritive value of the observed grasses in West Sumatra, Indonesia was relatively higher during rainy season compared with dry season. Pennisetum purpureum and Cynodon plectostachyus had the best nutritive value in both dry and rainy seasons.

• KSBB Journal
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• 제19권3호
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• pp.221-225
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• 2004

Bacillus sp. 유래의 Bacillus polyfermenticus SCD를 Bisroo $t^{ⓡ}$라고 부르고, 이것은 생균제로서 산업적으로 매우 유용하다. 본 연구에서는 B. polyfermenticus SCD를 산업적으로 활용성을 증대시키기 위해 three layer coating법을 사용하여 인공위액의 pH 변화에 대한 안정성과 열안정성, glucose 농도에 따른 안정성을 연구하였다. 그 결과 코팅한 B. polyfermenticus SCD가 인공위액에 대한 내성에서는 배양 4시간을 기준으로 pH 2는 30%, pH 4는 20%, pH 6은 14% 상승효과가 있었음을 알 수 있었고, 온도변화에 대한 안정성에서는 코팅한 B. polyfermenticus SCD가 8$0^{\circ}C$에서 2시간 기준으로 안정성이 약 40% 증진됨을 확인할 수 있었다. 고농도 (30%)의 glucose에서 코팅한 B. polyfermenticus SCD는 안정하였으며, 코팅하지 않은 것보다 약 50% 안정성이 증대됨을 확인할 수 있었다. 그리고 pH 4.0에서는 코팅한 B. polyfermenticus SCD는 코팅을 하지 않은 B polyfermenticus SCD보다 전체적으로 생존율이 40% 이상, pH 6.0에서는 생존율이 42% 이상 증진됨을 알 수 있었다.

• 산업식품공학
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• 제14권3호
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• pp.217-221
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• 2010

플라스크 실험과 fermentor 발효실험으로 분리균주인 Acetobacter aceti B20 균주의 초산발효를 위한 몇가지 조건을 최적화하였다. 통기교반 조건이 제한된 flask 실험에서 B20 균주의 생육은 에탄올 농도에 민감하게 반응하여 4%의 에탄올 농도에서는 거의 생육이 되지 않았으며, 초산 생성량도 미미하였다. Flask 배양에서 B20 균주의 생육은 포도당 농도가 3%일 때 가장 좋았으나 농도가 증가할 수록 생육이 저해되었다. ${27^{\circ}C}$와 ${30^{\circ}C}$의 온도에서 A. aceti B20 균주의 생육과 초산생성은 유사하였으며, 이보다 낮거나 높은 온도에서는 생육과 초산 생성이 모두 저하되었다. B20 균주의 최적 발효온도는 $27{\pm}3^{\circ}C$ 범위로 생각된다. Fermentor의 교반속도가 높아질수록 B20 균주의 생육도와 초산생성량이 증가하여 500 rpm일 때 초산농도 5.34%, 발효수율은 57.2%이었다. Batch식 발효에서 초기 에탄올 농도가 7%일 때 발효 120시간째 산도가 5.34%로 가장 높았으며, 이 때의 발효수율은 56.1%로 가장 양호하였다. Fedbatch식 발효에서 초산농도는 2회 feeding할 때 144시간째 8.76%로 최고에 도달하였으며, 이 때 발효수율은 50.6%로 feeding 횟수가 증가할수록 낮게 나타났다.

• 대한가정학회지
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• 제28권2호
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• pp.37-45
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• 1990

The purpose of this study was to determine the foaming properties of two small red bean protein isolates at various conditions. Data concerning the effects of pH, temperature, MaCl concentration, sugar concentration and protein concentration on the properties such as solubility, foam expansion, foam stability were presented. The results were summarized as follows : 1. The crude protein contents of two small red beans were 26.14% and 22.71%. The percentage of nonpolar amino acid group was the highest and that of sulfur containing amino acid group was the lowest. 2. Protein solubility showed the minimum at pH 4.5 which is isoelectric point of small red bean protein isolate adn heat treatment lowered solubility(P<0.05). At pH 4.5, solubility increased sighificantly as 0.4M NaCl was added. However, the effect of sugar concentration in the solubility was not significant. 3. Foam expansion of two small red bean protein isolates was high at pH 4.5 and heat treatment at 10$0^{\circ}C$ lowered foam expansion(P<0.05). While addition of NaCl, sugar did not affect the foma expansion, gradual increment of the protein isolates concentration up to 9% decreased the foma expansion slightly. 4. Foam stability was significantly high at pH 4.5 and heat treatment at 10$0^{\circ}C$ lowered foam stability. Addition of sugar caused slight decrease in foam stability. From 1% to 9% suspension, foma stability increased significantly as protein concentration increased(P<0.05)