• Archives of Pharmacal Research
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• 제24권1호
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• pp.69-73
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• 2001

Biodegradable hydrogels based on glycidyl methacrylate dextran (CMD) and dimethacrylate poly(ethylene glycol) (DMP) were proposed for colon-specific drug delivery. GMD was synthesized by coupling of glycidyl methacylate with dextran in the presence of 4-(N, N-dimethylamino)pyridine (DMAP) using dimethylsulfoxide as a solvent. Methacrylate-terminated poly (ethylene glycol) (PEG) macromer was prepared by the reaction of PEG with methacryloyl chloride. CMD/DMP hydrogels were prepared by radical polymerization of phosphate buffer solution (0.1 M, pH 7.4) of GMD and DMP using ammonium peroxydisulfate (APS) and UV as initiating system. The synthetic GMD, DMP and GMD/DMP hydrogels were characterized by fourier transform infrared (FT-lR) spectroscopy. The FITC-albumin loaded hydrogels were prepared by adding FITC-albumin solution before UV irradiation. Swelling capacity of GMD/DMP hydrogels was controlled not only by molecular weight of dextran, but also by incorporation ratio of DMP Degradation of the hydrogels has been studied in vitro with dextranase. FITC-albumin release from the GMD/DMP hydrogels was affected by molecular weight of nextran and the presence of dextranase in the release medium.

• 화약ㆍ발파
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• 제23권1호
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• pp.19-30
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• 2005

본 연구에서는 미진동파쇄기를 이용한 알반파쇄굴착공법의 기준 진동식과 암 분류에 따른 비장약량 산출식을 도출하였고 기존의 파쇄임도비율 산출식을 미진동파쇄기에 적합하도록 변환하였다. 그리고 표준암반파쇄패턴과 실시설계에 적용할 수 있는 공당장약량을 결정하였다 그 결과 자승근 환산식은 $V=345.39(D/\sqrt{W})^{-1.4484$, 비장약량 산출식은 $W_f=(2.3\~2.5)\;f_agdV$, 실시설계에 적용할 수 있는 공당장약량은 0.54kg, 직경 30cm의 파쇄입도비율은 약$48.7\%$로 산출되었다. 본 암반파쇄굴착공번은 타 공법에 비해 현장적 용성이 탁월한 것으로 사료된다.

• 한국환경과학회지
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• 제19권3호
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• pp.365-370
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• 2010

In this study, we carried out the evaluation of EPDM(Ethylene Propylene Diene Monomer) reclaimed rubber mixing with natural rubber at various mixing ratio to reuse as rubber filler. The scorch time and moony viscosity was analyzed to evaluate the effect of cure behavior. And also, we analyzed the tensile strength, the elongation at break and cure time to evaluate the variation of cure behavior. As the results, the scorch time and optimal cure time was decreased according to the increasing of EPDM reclaimed rubber. However, the moony viscosity was increased at each mixing ratio. In case of the added EPDM reclaimed rubber was 20 phr(parts by weight per 100 parts by weight of rubber), the hardness and specific gravity was increased a little. The hardness and specific gravity was increased in rapidly under 40 phr of the added EPEM reclaimed rubber. The tensile strength and elongation at break of the compound of natural and EPDM reclaimed rubber was rapidly decreased compared with its natural rubber when the ratio of adding EPDM reclaimed rubber was over 40 phr.

• Ocean and Polar Research
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• 제28권3호
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• pp.215-224
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• 2006

Spatial variation of heavy metal accumulation was investigated in Manila clam Ruditapes philippinarum collected from several tidal flats. Sediment metal levels varied highly among the sites, which was attributed primarily to differences in Fe and organic carbon contents and in part to gain size. Significant differences in metal concentrations also were found in the clam tissue among the different sampling sites. However, except for a few metals (Mn, Zn, Pb), which showed some elevation, the variations in the clam tissue were not related to the variations in the sediment. This is likely because most metals in filter-feeding herbivores such as R. philippinarum accumulated as a result of feeding on suspended particles such as phytoplankton and organic detritus in the water column, not in bottom sediment. In addition, tissue weight for a specific shell size varied significantly among the sites, and increased tissue mass indicating a good nutritive condition likely caused a subsequent dilution of body metals leading to reduced weight-specific concentrations of some metals (Cd, Zn, Cu, Co).

• 한국식생활문화학회지
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• 제16권5호
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• pp.478-482
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• 2001

This study was conducted to investigate the difference of general feature and ginsenoside content of 6 years old ginseng root among different grade of roots. Total weight of a 1st grade-6 years old ginseng root was 115.1g and weight, length, diameter and specific gravity of main root were 64.68g, 8.39cm, 3.31cm and 0.96, respectively. Main root of 1st grade ginseng root was larger in size and specific gravity and more heavy than that of End or 3rd grade of the roots. Though crude saponin contents were not so different among the different grade of roots, but ginsenoside Rb1, Rg1 and Re content were higher in 1st grade of root than that of 2nd or 3rd grade of root. Those ginsenosides were located mainly in periderm and cortex.

• 한국조리학회지
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• 제23권4호
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• pp.125-134
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• 2017

This study aimed to examine quality properties of muffin by the amount of addition of Korean whole wheat flour (0%, 25%, 50%, 75%, 100%) as there is increasingly higher interest in the healthy food. The effect of Korean whole wheat flour were evaluated in terms of height, volume, weight, specific volume, baking loss rate, colorimeter, and sensory evaluation. Texture and moisture contents of muffins when storage (1, 3, 5 days) was measured. As the ratio of Korean whole wheat flour increased, the baking loss rate and weight increased, whereas the volume and specific volume was not significant. During storage, moisture content of muffins decreased significantly. The addition of Korean whole wheat flour increased lightness (L value) of crust and crumb decreased, whereas redness (a value) and yellowness (b value) increased. The control group (CON) showed the highest springiness lowest hardness. The muffin with 25% of Korean whole wheat flour (WHF25) in test group showed the high springiness low hardness. According to the sensory evaluation, the control group showed the highest score in terms of taste, however WHF25 showed the highest score in appearance, color, flavor, texture and overall acceptance, WHF25 showed the best result and the optimum addition of Korean whole wheat flour. Furthermore, this study proposes the possibility of development of various confectionery with using Korean whole wheat flour.

• Archives of Pharmacal Research
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• 제18권5호
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• pp.320-324
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• 1995

Pretreatment of Glycyrrhizae Radix(GR) to male Sprague-Dawley rats was demonstrated to increase excretion of acetaminophen-glucuronide ocnjugate when bile nad urine were assayed after administration of acetaminophen. In order to study the effect of GR on the glucuronidation in rats, we examined enzymatic activities of hepatic UDP-glucuronosyl-transferases (UDP-GT1 and UDP-GT2) and intracellular concentrations of hepatic UDP-glucuronic acid (UDP-GA), upon the administration of GR (1 g/kg body weight, p.o.) or glycyrrhizin (23 mg/kg body weight, p.o.) a major component of GR, for 6 days. GR and glycyrrhizin caused increases in specific activities of UDP-GT2 111% and 96% respectively. Specific activity of UDP-GT1 was increased 25% by GR treatment whereas it was not significantly increased by glycyrrhizin. Concentrations of UDP-GA were increased 257% by GR and 484% by glycyrrhizin. These data indicate that GR activated glucuronidation and thus suggest the possibility that GR may influence detoxification of xenobiotics in rat liver.

• 한국정보통신학회논문지
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• 제18권7호
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• pp.1628-1633
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• 2014

본 연구는 스마트폰환경에서 사용자의 관심주제와 읽기습관을 분석하여 읽기 습관을 분석하여 관심 있는 뉴스기사를 추천 시스템을 제안하였다. 사용자가 직접 관심영역의 가중치를 정함으로서 관심주제의 기사를 우선적으로 보여 주어 사용자가 쉽게 관심기사를 읽을 수 있도록 하였다. 또한 사용자가 사회적으로 이슈가 되는 기사에 관심을 갖는 경우 이를 반영하기 위해서 단순히 기사를 클릭하고 읽지 않은 경우는 가중치를 낮게 설정하였으며, 기사를 끝까지 스크롤을 하고 기사를 끝까지 읽은 경우는 가중치를 높게 설정하였다. 특정 분야의 기사를 자주 읽은 경우는 XML의 구조정보를 사용하여 관심주제영역의 가중치를 높게 설정함으로써 관련분야의 기사를 우선적으로 볼 수 있도록 하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.747-750
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• 2004

Lightweight concrete is known for its advantage of reducing the self-weight of the structures, reducing the areas of sectional members as well as making the construction convenient. Thus the construction cost can be saved when applied. to . structures such as long-span bridge and high rise buildings. However, the lightweight concrete requires specific design mix method that is quite different from the typical concrete, since using the typical mix method would give rise the material segregation as well as lower the strength by the reduced weight of the aggregate. In order to avoid such problems, it is recommended to apply the design mix method of high performance self-compacting concrete for the lightweight concrete. Therefore, this study introduces a production of self-compacting concrete, PF-modified and improved version of Nan-Su's design mix method of self-compacting concrete. Through a series of test mixes conducted during the study, the quality of the concrete at its fresh condition has been evaluated per the 2nd class rating standards of self-compacting concrete published by JSCE, especially focused in its fluidity, segregation resistance ability, and filling ability.

• Fibers and Polymers
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• 제5권4호
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• pp.280-288
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• 2004

Split-type nylon/polyester microfiber and polyester microfiber fabrics possess drapeability, softness, bulkiness, and smoothness, so that they can be applied in various industrial fields. In particular, these fabrics are able to absorb various organic solvents, and can be used as clean room materials. To investigate the chemical affinity between solvents and the compositional materials of these fabrics, the contact angle of thermally pressed film fabrics was measured with different solvents. The thermally pressed nylon/polyester fabric films showed a chemical attraction to formamide. The sorption properties of the microfiber fabrics were investigated using a real time testing device, and these tests showed that the sorption behavior was more influenced by the structure of the fibrous assembly than by any chemical attraction. The effect of the fabric density, specific weight, and sample structure on the sorption capacity and rate was examined for various organic solvents. The sorption capacity was influenced by the density and the specific weight of the fibrous assembly, and knitted fabric showed a higher sorption capacity than woven fabric. However, the sorption rate was less affected in lower viscosity solvents. On applying Poiseuille's Law, the lower viscosity solvents showed higher initial sorption rates, and more easily penetrated into the fibrous assembly.