• 한국환경보건학회지
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• 제38권2호
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• pp.136-141
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• 2012

Objectives: The objective of this study was to investigate whether the ammonia nitrogen concentration of aqueous samples such as drinking water can be determined by measuring the saturation of the samples colored by indophenol method. Methods: A color saturation measurement system was constructed by connecting a notebook computer to an image acquisition device composed of a PC camera and a light source, and was then used to measure the saturation of samples colored by blue indophenol complex. Results: Between two available light sources, a fluorescent lamp was selected due to its demonstrating better linearity between color saturation and ammonia nitrogen concentration. Prediction by quadratic regression was more accurate than by linear regression, and prediction by quadratic regression in the concentration range of 0.1-1.0 $mg/l$ was more accurate than in the concentration range of 0.0-1.0 $mg/l$. Regression-based predictions over 0.25 $mg/l$, 0.55 $mg/l$ and 0.75 $mg/l$ concentrations were implemented both by spectrophotometric method and by measuring color saturation. In the case of 0.25 $mg/l$, the predicted concentration by spectrophotometric method was $0.256{\pm}0.0076\;mg/l$ and the predicted concentration by measuring color saturation was $0.246{\pm}0.0086\;mg/l$ (p=0.051). In the case of 0.55 $mg/l$, they were $0.561{\pm}0.0068\;mg/l$ and $0.564{\pm}0.0166\;mg/l$ (p=0.660). In the case of 0.75 $mg/l$, they were $0.755{\pm}0.0139\;mg/l$ and $0.762{\pm}0.0088\;mg/l$ (p=0.215). Conclusions: There were no statistically significant differences (p>0.05) between the data from the two methods in all three of the concentrations. Therefore, the color saturation measurement method proposed in this paper may be considered applicable for determining the ammonia nitrogen concentration of aqueous samples such as drinking water.

• 공업화학
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• 제2권3호
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• pp.209-215
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• 1991

n-헥산과 40 wt % p-TSA 수용액으로 이루어진 비혼화성 액상계에서 교반에 의한 유기상의 분산을 해석하였다. 사용된 교반기는 blade의 형태가 flat와 금망으로 된 4가지 형태의 6-bladed turbine 교반기를 사용하였다. 실험결과, 동일한 교반속도에서 유기상의 분산정도는 blade의 형태가 flat, 60 mesh, 40 mesh, 20 mesh의 순서로 감소하였고 계면활성제인 TBA의 농도가 증가할수록, 그리고 유기상의 부피비가 작을수록 유기상은 잘 분산되었다. 또한 완전분산에 필요한 최소교반속도는 flat, 60 mesh, 40 mesh, 20 mesh의 순서로 증가하였으나 최소소요동력은 거의 동일하였다. 이때 Power number와 Reynolds number와의 관계는 $N_p=a\;N_{Re}{^b}$ 이었으며 교반기의 형태에 따른 상수 a와 혼합계의 종류에 따른 상수 b의 값은 각각 2200~4100, -0.69~-0.63 범위이었다.

• 한국식품과학회지
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• 제30권2호
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• pp.434-438
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• 1998

Linoleic acid 1% 완충용액에 3종의 phenolic acid류, 즉 caffeic acid, ferulic acid, vanillic acid 및 인삼 추출물에 대한 산화방지 효과를 비교물질로 ${\alpha}-tocopherol$을 사용하여 MDA (malondialdehyde) 정량법과 headspace oxygen analysis로 측정 비교 하였다. MDA 생성량으로 비교한 산화방지 효과는 $caffeic\;acid{\geq}ferulic\;acid>{\alpha}-tocopherol>$인삼 추출물>vanillic acid 순으로 나타났으며, 이때 산화저해율은 각각 63.5, 62.9, 52.3, 51.2, 5.6% 이었다. 첨가된 인삼 추출물의 농도는 700 ppm, 그외 phenolic aicd류 및 ${\alpha}-tocopherol$의 농도는 각각 100 ppm 이었다. 또한 인삼 추출물에 caffeic acid와 ${\alpha}-tocopherol$을 각각 100 ppm 첨가한 결과 91.2%의 산화저해율을 나타내었다. Headspace oxygen analysis 에 따른 결과에서는 MDA 생성량으로 비교한 산화방지 효과와 유사한 경향으로 나타났으며, ferulic acid>caffeic acid>${\alpha}-tocopherol$>인삼 추출물>vanillic acid의 순 이었고, 이때의 headspace 중 산소 함량은 18.56, 17.78, 17.17, 16.65, 15.95%로 각각 나타났다.

• 대한본초학회지
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• 제25권3호
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• pp.11-18
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• 2010

Object : This study was to evaluate the effect of Ginseng Radix, aqueous extracts of the root part of Panax ginseng on the 6-n-propyl-2-thiouracil(PTU)-induced rat hypothyroidism. Methods : Aqueous extracts of Ginseng Radix(GR; yield = 11.70%) were administered, once day for 42 days from 2 weeks before start of PTU treatment as an oral dose of 300 and 150 mg/kg(body weight), and hypothyroidism was induced by daily subcutaneous treatment of PTU 10mg/kg for 28 days. The changes in the body weight, thyroid gland weights, serum levels of thyroid hormone-thyroid stimulating hormone(TSH), tri-iodothyronine(T3) and thyroxine(T4), total cholesterol, low density lipoprotein(LDL), high density lipoprotein(HDL) and triglyceride, liver antioxidant defense system-lipid peroxidation, $H_2O_2$, superoxide dismutase(SOD) and catalase(CAT) were observed with histopathology of thyroid glands. Results : Results were compared with LevoT4 0.5mg/kg treated rats. GR extracts suppressed the decreases in the body weight, thyroid gland weights, T3 and T4, TG, liver $H_2O_2$ and SOD activities as results of PTU treatment. And GR extracts suppressed the increases of HDL contents, liver CAT activities, thyroid gland weight as results of PTU treatment. In addition, marked hyperplasia of follicular cells with decreases of follicular colloid contentsand sizes were demonstrated at histopathological inspections. However, these PTU-induced histopathological changes related to hypothyroidism were dramatically decreased by treatment of both different dosages of GR extract, respectively Conclusions : This study suggest that GR extracts have favorable effects on the thyroid hormone productions with beneficial effects on the hypothyroidism mediated by the modulatory effects on the antioxidant defense system.

• 한국재료학회지
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• 제11권8호
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• pp.679-684
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• 2001

천연흑연은 단위구조가 탄소육각망평면이 평행하게 배열된 층상으로 전기전도도 및 윤활성이 우수하나 소수성이 매우 강하며, 표면화학적 목성이 거의 없기 때문에 다른 물질과 흡착이 쉽게 일어나지 않아 분산이 매우 어려운 물질이다. 따라서 본 연구에서는 제타전위를 이용하여 흑연에 ABDM을 흡착시켜 표면특성을 소수성에서 친수성으로 변화시키고 수중현탁액 중에서 흑연입자의 분산 메커니즘을 DLVO이론을 이용하여 설명하였다. 흑연의 제타전위가 22.5mV가 되도록 ABDM의 흡착량 (20mg/g) 및 조건 (PH 10에서 12시간 흡착)을 만족시키면 분산안정성 (T$_{1/2}$) 이 44.5시간인 고분산성 흑연 현탁액을 제조할 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1875-1877
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• 2001

Glaucoma is an eye disease which is caused by abnormal high lOP (Intra Ocular Pressure). High lOP is caused by the aqueous humor which is produced consistently but not drained due to malfunction of the trabecular system which has a role of draining the aqueous humor into the venous system. Currently, there are some methods to treat glaucoma, Among these, the use of implants is increasing in these days due to many problems In other methods. However, conventional implants are passive implants and have critical disadvantage. Therefore, it is needed to develop an active implant which is composed of a valve actuator, pressure sensor, controller, and power supply. In this paper, we make experiment with the fabricated valve actuator in In-vitro experiment, and estimate the in-vivo result using the experimental result and investigate the possibility of the fabricated valve.

• Advances in Traditional Medicine
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• 제7권1호
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• pp.51-64
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• 2007

Mucus is an aqueous gel complex with a constitution of about 95% water, high molecular weight glycoprotein (mucin), lipid, salts etc. Mucus appears to represent a significant barrier to the absorption of some compounds. Natural mucoadhesive agent was isolated and purified from the aqueous extract of the seeds of prosopis pallida (PP). Formulated tablet with the isolated material by wet granulation method. Some natural edible substances are in consideration for candidates as mucoadhesive agents to claim more effective controlled drug delivery as an alternative to the currently used synthetic mucoadhesive polymers. Subjected the materials obtained from natural source i.e. PP and standard synthetic substance, sodium carboxymethyl cellulose for evaluation of mucoadhesive property by various in vitro and in vivo methods. Through standard dissolution test and a model developed with rabbit, evaluated in vitro controlled release and bioadhesive property of theophylline formulation. Mucoadhesive agent obtained from PP showed good mucoadhesive potential in the demonstrated in vitro and in viνo models. The results suggest that the mucoadhesive agent showed controlled release properties by their application, substantially. In order to assess the gastrointestinal transit time in vivo, a radio opaque X-ray study performed in healthy rabbit testing the same controlled release formulation with and without bioadhesive polymer. Plasma levels of theophylline determined by the HPLC method and those allowed correlations to the in vitro mucoadhesive study results. Better correlation found between the results in different models. PP may acts as a better natural mucoadhesive agent in the extended drug delivery system.

• 대한한방부인과학회지
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• 제28권2호
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• pp.55-75
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• 2015

Objectives : The object of this study was to evaluate the effect of Insamyangyoung-tang aqueous extracts (ISYYT) on the propylthiouracil (PTU) induced rat hypothyroidism. Methods : The rats were divided into 6 groups : intact control, PTU control, Levothyroxine (LT ₄ ), 500, 250 and 125 mg/kg ISYYT treated groups. In ISYYT treated groups, PTU and ISYYT were administered for 4 weeks after 500, 250 and 125 mg/kg ISYYT were administered for 2 weeks. In LT ₄ group, PTU and LT ₄ were administered for 4 weeks. The changes were observed : the weigh, serum thyroid hormone levels, serum sex hormone levels, serum lipid profiles, serum liver enzyme levels, liver and testis antioxidant defense system, histopathology of thyroid gland, liver, epididymis, prostate and testis. Results were compared with PTU control group in this experiment. Results : In comparison with PTU control group, 500 and 250 mg/kg ISYYT treated groups showed significant increase of body, thyroid, liver, testis, epididymis and prostate weights, decrease of serum TSH levels with increase of serum T3 and T4 level, increase of serum testosterone and DHT levels with decrease of serum FSH levels, decrease of serum HDL with increase of TG and increase of serum AST levels. Histopathological inspections of hepatic and male reproductive organ damage induced by PTU were improved. And the changes of antioxidant defense system of Liver and testis induced by PTU were improve. There was no significant difference between 125 mg/kg ISYYT treated group and PTU control group in this experiment. Conclusions : The results obtained in this study considered that Insamyangyoung-tang may be effective in hypothyroidism and related organ damages.

• 공업화학
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• 제5권1호
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• pp.127-138
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• 1994

CTA(cellulose triacetate) 막을 이용한 물과 에탄올의 투과증발(pervaporation) 막분리에서 수착과 투과실험으로부터 용해-확산 투과기구modeling 및 그 함수형과 parameters에 대한 해석을 시도하였다. 순성분들의 수착 data를 사용하여 Flory-Huggins 식으로 계산한 3 성분계(에탄올/물/CTA) 수착평형 조성을 추산하여 실측치와 비교하였다. 막 내부의 조성과 액상의 평형 조성간에 열역학적 평형 관계식을 적용하기 위해 막 내 겉보기 활동도를 Wilson식과 Van Laar식으로 상관시켰다. 투과속도식은 한 성분의 투과속도가 그 성분의 막 내 농도구배에 비례하며, 또한 확산계수의 농도 의존성이 에탄올 농도만의 지수함수라고 가정하여 물과 에탄을 투과속도를 계산하였으며 이는 실측치와 잘 일치하였다. 한 성분의 투과속도와 수착량이 다른 성분에 비해 현저히 작은 경우에는 대류항을 무시할 수 없음을 알았고, 온도가 높고, 투과측 압력이 낮을수록 투과속도와 투과선택도가 증가하였다.

• 동의생리병리학회지
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• 제29권5호
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• pp.394-402
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• 2015

To evaluate the benefits of Hyangsayangyi-tang aqueous extracts (HSYYT) on the propylthiouracil (PTU)-induced Rat hypothyroidism. 6 groups, each consisting 8 Rats were used in the present study - Intact vehicle control, PTU control, LT₄, HSYYT 500, 250 and 125 ㎎/㎏ treated groups. HSYYT was given, once day for 42 days from 2 weeks before start of PTU treatment as an oral dose of 500, 250 and 125 ㎎/㎏(body weight), and for 28 days while the PTU 10 ㎎/㎏ by daily subcutaneous treatment induced hypothyroidism. Compared the results with LT₄ 0.5 ㎎/㎏ intraperitoneally treated rats in this experiment. Results of the PTU treatment included; decreases of body weight, increase in thyroid weight, decrease in liver weight, in serum T₃, and T₄ level decrease with increase of serum TSH levels, in serum HDL increase and in TG content decrease, decrease in liver antioxidants defense system, increase of serum AST levels were observed. However, these PTU induced hypothyroidism and related hepatic damages were dose-dependently inhibited by treatment of HSYYT 500 and 250 ㎎/㎏, and they also effectively regulated the PTU-induced abnormal antioxidant defense system changes in liver. Therefore, in comparison with the PTU control group, it was effective and advantageous changes were not observed in HSYYT 125 ㎎/㎏ treated rats on the PTU induced hypothyroidism and related hepatic damages. In this experiment, HSYYT 500 and 250 ㎎/㎏ dose-dependently inhibited PTU-induced hypothyroidism and related liver damage in rats but not in HSYYT 125 ㎎/㎏.