• 대한환경공학회지
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• 제31권12호
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• pp.1135-1142
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• 2009

본 연구는 고분자 응집제를 이용하여 짧은 시간에 입상형태의 슬러지를 제조한 다음, 입상슬러지를 호기성 입상화 장치에 주입하여 입상화를 시도하였다. 각 반응조에서 호기성 입자의 형성에 따른 입자의 크기, 밀도, 입자내 미생물 체외분비 고분자물질 등의 물리.화학적인 특성을 조사하였다. 입상형태의 슬러지를 호기성 입상화 장치에 주입하여 COD 부하량 3, 6, 9 $kg{\cdot}COD/m^3{\cdot}d$로 35일간 운전한 결과 최종 형성된 호기성 입장의 평균 크기는 각각 3.6 mm, 4.3 mm, 3.4 mm 이었고 호기성 입자의 침강속도는 각각 1.5 cm/s, 1.6 cm/s, 1.2 cm/s 이었다. COD 부하량에 따른 미생물 군집체의 비성장속도는 0.12 $d^{-1}$, 0.135 $d^{-1}$, 0.133 $d^{-1}$이었으며 전반적으로 호기성 입상화 장치에서는 COD 부하량이 $6kg{\cdot}COD/m^3{\cdot}d$로 운전된 반응조에서 호기성 입자의 물리 화학적인 특성이 우수하였다.

• 대한환경공학회지
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• 제38권10호
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• pp.574-579
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• 2016

생활하수슬러지만 소각하는 시설에서 발생되는 비산재를 비료 제조시 주원료 또는 부원료로 활용하기 위해 비산재를 원료로 비료를 제조하고 구성성분을 분석하였다. 비산재를 포함해 제작된 비료의 구성 및 물성, 강도, 중금속에 대한 위해성 등을 분석하였다. 비산재는 충분한 인을 함유하여 비료의 원료로 사용될 수 있으나, 비산재를 주원료(40% 이상 포함)로 비료를 제작할 경우 조립화율(2-4 mm 입자 형성율)을 80% 이상 달성할 수 없었다. 비산재를 보조원료로 첨가하여 비료를 제조할 경우, 비산재 함유량을 15%이하로 유지하면 조립화율을 80% 이상 달성할 수 있었다. 비산재를 보조원료로 조립화된 비료의 중금속 분석결과, 폐기물공정시험기준인 용출실험에서는 위해성이 없는 것으로 나타났다. 그러나 토양오염공정시험의 함량분석 상으로는 비산재 함유량이 높아짐에 따라 카드뮴 등 중금속 위해성을 초과하는 항목이 발생되었다. 따라서 비료제작시 비산재를 보조원료로 투입할 경우 중금속을 제거하기 위한 전처리를 하지 않는다면 비료원료의 비산재 함유량을 7% 이하로 유지하는 것이 바람직하다.

• Journal of Pharmaceutical Investigation
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• 제39권1호
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• pp.7-12
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• 2009

A novel polymeric tablet of Tinidazole was formulated to treat Helicobacter pylori and Giardia lambria more efficiently, It was possible to reduce hepatotoxicity by controlling the release of Tinidazole after peroral administration. A gastric retentive formulation made of naturally occurring carbohydrate polymers and containing Tinidazole was tested in vitro for swelling and dissolution characteristics. Tinidazole tablets containing various concentration of either PEO or HPMC were prepared by the wet granulation method. In vitro release of Tinidazole at pH 1.2 and pH 6.8 buffer solutions was observed at $37^{\circ}C$ by using a KP dissolution method and an UV (313 nm) spectrophotometer. Compared to a commercial Tinidazole tablet, in vitro release of Tinidazole at both pH 1.2 and pH 6.8 buffer solutions significantly decreased as the concentration of PEO or HPMC in the tablet increased up. And the gastric retentive formulation hydrated and swelled back to about 50% of its original size in 30 min. Thus, it was possible to control the release of Tinidazole by changing the content of PEO or HPMC in the tablet, thereby manipulating the release rate and the retention of Tinidazole.

• 디자인학연구
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• 제16권2호
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• pp.291-300
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• 2003

동합금을 이용한 금속공예기법에는 성형기법 세공기법이 있다. 이러한 기법에는 주조기법(Metal casting)과 단금기법이 있는데, 주조기법에는 사형(Sand mould, 토범-중국은 도범, 일본은 물형, 납형), 석형, 안틀 끼우기(입형)와 안틀 깎기(삭중형) 등이 있다. 단금기법에는 단조기법 추기기법, 판금기법 등이 조사되었으며, 세공(장식)기법으로는 조금기법, 선조기법, 점선조기법 등이 조사되었다. 이와 더불어 모조기법, 축조기법, 어자문기법과 세선 세공 및 세입세공을 바탕으로 하는 누금세공기법이 주로 사용 되었음이 밝혀지고 있다. 한국의 전통적인 동합금의 방식에 있어서도 성형기법과 세공기법을 주로 사용하는 특성이 있다. 한국에서는 전통적으로 청동을 사용하여 합금을 시도한 바 있으며, 일본의 경우는 자입착색법을 바탕으로 하는 방식을 주로 하여 제작하며, 중국의 경우는 청동합금기술을 바탕으로 하는 방식을 선호하여 제작하였다. 합금방식에 있어서는 3국 모두 각기 독특한 방식을 사용하고 있으나, 한국의 경우는 청동을 주로 사용하되 현대에 와서는 동합금을 주로 사용하고 일본의 경우는 시부이치와 샤큐도우를 주로 사용하여 착색을 시도하여 그 표현방식이 독특하게 이루어 졌다. 중국의 경우는 동을 사용하되 황동과 백동을 주로 사용하여 특징적인 작품세계를 구축하였다.

• Journal of Microbiology and Biotechnology
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• 제17권10호
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• pp.1661-1669
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• 2007

Gamma-aminobutyric acid (GABA) is a non-protein amino acid. It is well known for its role as an inhibitory neurotransmitter of developing and operating nervous systems in brains. In this study, a novel function of GABA in the healing process of cutaneous wounds was presented regarding anti-inflammation and fibroblast cell proliferation. The cell proliferation activity of GABA was verified through an MTT assay using murine fibroblast NIH3T3 cells. It was observed that GABA significantly inhibited the mRNA expression of iNOS, IL-$1{\beta}$, and TNF-${\alpha}$ in LPS-stimulated RAW 264.7 cells. To evaluate in vivo activity of GABA in wound healing, excisional open wounds were made on the dorsal sides of Sprague-Dawley rats under anesthesia, and the healing of the wounds was apparently assessed. The molecular aspects of the healing process were also investigated by hematoxylineosin staining of the healed skin, displaying the degrees of re-epithelialization and linear alignment of the granulation tissue, and immunostaining and RT-PCR analyses of fibroblast growth factor and platelet-derived growth factor, implying extracellular matrix synthesis and remodeling of the skin. The GABA treatment was effective to accelerate the healing process by suppressing inflammation and stimulating re-epithelialization, compared with the epidermal growth factor treatment. The healing effect of GABA was remarkable at the early stage of wound healing, which resulted in significant reduction of the whole healing period.

• 한국분말재료학회지
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• 제16권1호
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• pp.22-27
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• 2009

To improve the filtration efficiency of porous materials used in filters, an extensive specific surface area is required to serve as a site for adsorption of impurities. In this paper, a method for creating a hybridized porous alloy using a powder metallurgical technique to build macropores in an Al-4 wt.% Cu alloy and subsequent surface modification for a microporous surface with a considerably increased specific surface area is suggested. The macropore structure was controlled by granulation, compacting pressure, and sintering; the micropore structure was obtained by a surface modification using a dilute NaOH solution. The specific surface area of surface-modified specimen increased about 10 times compare to as-sintered specimen that comprised of the macropore structure. Also, the surface-modified specimens showed a remarkable increase in micropores larger than 10 nm. Such a hybridized porous structure has potential for application in water and air purification filters, as well as membrane pre-treatment and catalysis.

• Journal of Pharmaceutical Investigation
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• 제38권3호
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• pp.157-162
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• 2008

The aim of the study was to formulate the stable amlodipine maleate tablet by selecting and combining of suitable ingredients. Amlodipine tablets were designed by using different manufacturing methods or formulations. Dissolution rate at 30 min of newly formulated tablets was over 98% in 0.1 M HCl medium. After 4 months storage under accelerated condition, the changes of appearance, loss on drying, content and total impurity were investigated. For long-term stability tests, two formulations of K017 (direct compressed tablets consisting of microcrystalline cellulose and pregelatinized starch) and K018 (wet granulated tablets by OpadryAMB) were stored under $25^{\circ}C$, 60% RH for 24 months. Under the accelerated condition, moisture content in K017 formulation was increased as 5.96% for 4 months, while other formulations with anhydrous monobasic phosphoric potassium or by wet granulation showed higher increase in moisture content compared to K017. In addition, K017 formulation showed a low decrease in contents and total relative substance as 0.8% and 0.7%, respectively. Similar stability of amlodipine in K017 was obtained under the long-term stability test. These results indicate that the K017 combined with microcrystalline cellulose and pregelatinized starch as ingredients is very stable formulation to protect active substance from moisture contact and sustain stability. Therefore, suitable combination of ingredients such as microcrystalline cellulose and pregelatinized starch could attribute to enhance the stability of moisture-labile drug such as amlodipine maleate.

• Fisheries and Aquatic Sciences
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• 제6권2호
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• pp.81-87
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• 2003

Experiments were carried out to investigate the accumulation and the histopathological changes in liver of juvenile rockfish, S. schlegeli, after sub-chronic dietary Cu (0, 50, 125, 250 and 500mg/kg) exposure for 60 days. Cu accumulation in liver was significantly increased with dietary exposure period and concentration for 60 days, and has a linear relation with dietary exposure days. After 60 days of Cu dietary exposure, the Cu concentration in the liver was $75.9\pm12.05,\;126.29\pm22.11\;and\;360.44\pm45.26\;{\mu}g/g$ dry weight and was approximately 11-fold, 18-fold and 51-fold higher than in the control diet group at 125, 250 and 500 mg/kg Cu diet group. The accumulation factors were increased with the dietary exposure period in liver of rockfish. In the primary exposed stage, the effect of hepatic tissue in the rockfish exposed to dietary Cu observed enlargement of hepatocytes nuclei, activity of hepatic cells and the swelling of hepatic cells. While exposed time and concentration were increased, the distinct granulation, irregular shape and necrosis of hepatic cells were observed. It was observed that granule degeneration and necrosis showed a part of cells in hepatic tissue after 60 days at 500 mg/kg.

• Journal of Pharmaceutical Investigation
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• 제41권2호
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• pp.67-73
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• 2011

Ion exchange resins can be one of the good carriers for sustained drug release. However, the sustained release may not be enough only with themselves and hence film coating with rate controlling polymers can be applied to have a further effect on the drug release. Due to the environmental and economic issues of organic solvent for the polymer coating, aqueous polymeric systems were selected to develop dosage forms. Among the many aqueous polymeric dispersions for the film coating, EC (ethylcellulose) based polymers such as Aquacoat$^{(R)}$ ECD and Surelease$^{(R)}$ were evaluated.A fluid-bed coating was applied as a processing method. The drug release rate was quite dependent on the coating level so the release rate could be modified easily by changing different levels of the coating. The drug release rate in the Aquacoat$^{(R)}$ coated resin particles was strongly dependent on curing, which is a thermal treatment to make homogeneous films and circumvent drug release changes during storage. After dissolution test using the compressed tablets in which the coated resin particles are contained, inhomogeneous coating and even pores could be observed showing that the mechanical properties of EC were not resistant to granulation and compaction process. However, when tablets were prepared in different batches, the release profiles were almost identical showing the feasibility of the coated resin particle as incorporated into the tablet formulation.

• Journal of Pharmaceutical Investigation
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• 제39권6호
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• pp.445-449
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• 2009

According to the statistical data, stroke is about 13.9% of leading causes of death. Some herbal medicines including Paeonia lactiflora, Angelica gigas nakai and Prunus persica, etc., had been reported to be effective in preventing stroke and mBHT (Modified BoyangHwanoTang) was an advanced prescription used in Korean clinics. Orally disintegrating tablets (ODT) is useful for patients suffering from dysphagia, motion sickness, repeated emesis and mental disorders. Further, drugs exhibiting satisfactory absorption through the mucosa intended for immediate pharmacological action could be advantageously formulated in ODT. The aim of this study was to develop the most efficient ODT formulation of mBHT. Corresponding herbal medicines comprising mBHT were extracted with water for 3 hr at 95~$100{^{\circ}C}$ and then dried. mBHT extract was obtained with about 30% of yield. Subsequently, some pharmaceutical excipients such as spray-dried lactose, crospovidone, glyceryl behenate and/or cogrinded-treated arabia gum were used to achieve an immediate disintegration of mBHT ODT in oral cavity. The requirements of ODT with mechanical strength sufficient to stand the rigors of handling and capability of disintegrating within a few seconds in contact with saliva are indispensable. mBHT ODT prepared by the wet granulation method showed a disintegration time of below 30 sec.