• 한국식품저장유통학회지
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• 제19권4호
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• pp.485-491
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• 2012

복숭아를 이용한 고부가가치 제품의 개발을 위하여 복숭아의 냉풍 및 적외선 건조 방법에 따른 품종별 건조 복숭아의 품질 특성을 조사하였다. 건조 방법에 따른 품종별('천홍', '유명') pH 및 가용성 고형분 함량은 전반적으로 적외선 건조에서 냉풍 건조 보다 높게 나타났으며, '천홍' 품종보다 '유명' 품종에서 pH 및 가용성 고형분 함량이 높은값을 나타내었다. 색도는 L과 ${\Delta}E$ value은 적외선 건조에서 높게 나타났고, 반면에 a, b value는 냉풍건조에서 높은 값을 보였다. 유리당 분석결과 조성은 sucrose > fructose > glucose 순이었고, 그 함량은 sucrose에서 50.71 mg/100 g으로 가장 높게 나타났으며, 적외선 건조가 냉풍 건조에 비해 전반적으로 높은 함량을 나타내었다. 유기산은 품종 및 건조 방법에 상관없이 oxailic acid, malic acid, citric acid가 동정되었으며, 그 중 citric acid 함량이 6.17 mg / 100 g으로 가장 높게 나타났다. 무기질은 모든 조건에 상관없이 K의 함량이 높게 나타났으며, 그 조성은 K > Mg > Ca > Na > Fe > Zn > Cu > Al의 순으로 나타났다. 전반적으로 적외선보다 냉풍 건조에서 높게 나타났고, '천홍'보다 '유명' 품종에서 함량이 높게 나타났다. 관능검사 결과 외관과 맛은 적외선 건조에서 높게 평가되었고, 색도와 조직감에서는 냉풍 건조에서 높게 평가되었다. 또한 NaCl로 전처리하였을 때 기호성이 높게 평가되어 건조와 함께 전처리를 병용하면 건조 과실의 기호성 향상에 기여할 것으로 생각된다. 이상의 결과에서 적외선 건조 방법으로 제조한 건조 복숭아의 품질이 전반적으로 우수하다고 판단되며, 건조 복숭아 제조 방법으로 적합할 것이라 사료된다.

• Journal of Korean Society for Atmospheric Environment
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• 제11권E호
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• pp.13-21
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• 1995

This Pilot study identifies potential dioxin and furan sources and medical plastic wastes produced from hospital solid waste streams. In this study, air emissions of dioxins and furans from sources in the U.S., which were estimated by the U.S. Environmental Protection Agency (EPA), were summarized. Potential loading routes of dioxins and furans to the U.S.-Canada Great Lakes region have also been identified in trcent surveys. In addition, medical and hospital solid wastes produced in typical large city hospitals were characterized as important potential sources of dioxins and furans. Plastic contents in medical Plastics Characterization Survey (MMPCS), plastics composition data were obtained from a survey of five Massachusetts Hospitals and Medical Centers. By identifying plastic wastes as a percentage of total hospital wastes, we were able to use data from a preliminary study that analyzed the waste stream of 16 major New York City hospitals (NYCMWS) characterizing the plastic content of the wasters. This study determined the types of plastic wastes included in each medical waste stream (regulated medical waste or non regulated medical waste) and it discussed the potential for recyclibility of hospital plastic wastes. The combination of the NYCMWS and the MMPCS surveys provides for the first overview of the size of the recycling task of hospital plastic wastes and the potential of dioxin elimination if dioxin generating plastics were to be eliminated from hospital use.

• 한국연소학회지
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• 제13권2호
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• pp.23-32
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• 2008

Gasification characteristics in the fluidized bed reactor are essential for the design of a gasification furnace to optimize the operation condition. Moisture content of the solid fuel is one of the important factors to influence directly the gasification characteristics. So it is necessary to investigate the effect of moisture content of solid fuel in partial oxidation condition. Gasification characteristics are investigated with results from thermogravimetric analyzer and lab-scale fluidized bed reactor for wood and RDF samples along with changing moisture contents. Additionally lab-scale fluidized bed reactor was run continuously and gas concentrations at the exit were measured. It is observed that the rate of reaction in partial oxidation condition is between the results from the combustion environment and from the inert condition. Moisture content in a particle slows down the heating rate of a particle. So, reaction is delayed by the moisture content. However, RDF samples those are easy to break-up don't show the effect of moisture content. The result of continuous operation condition shows that proper moisture content promotes gasification because steam from the particles helps gasification of the solid fuel. A simulation to predict the syn-gas composition was conducted by the Aspen Plus process simulator. The cold gas efficiency of the experiment was compared with results from the simulation.

• Journal of Pharmaceutical Investigation
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• 제20권1호
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• pp.13-18
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• 1990

Hydrocortisone (HC) sustained-release suppositories were prepared by using a solid matrix of methacrylic acid-methacrylic acid methyl ester copolymer $(Eudragit\;L_{100}^{R}:\;EL)$ as a poorly water soluble carrier and polyethylene glycole 1540 (PEG) as an water soluble carrier. HC release rate was controlled by complexation with ${\beta}-cyclodextrin$ $({\beta}-CyD)$ which was confirmed by X-ray diffractometry, IR-spectroscopy and differential scanning calorimetry. Release rate of HC from the EL-PEG matrix suppositories decreased with increase of EL contents. The release rale from $HC-{\beta}-CyD$ complex decreased in the following order: $HC-{\beta}-CyD/PEG$ > HC/PEG > $HC-{\beta}-CyD/EL_{10%}-PEG$ > $HC/EL_{10%}-PEG$ > $HC-{\beta}-CyD/EL_{15%}-PEG$ > $HC/EL_{15%}-PEG$ > $HC-{\beta}-CyD/EL_{20%}-PEG$ > $HC/EL_{20%}-PEG$. The crystallinity of HC in polymer matrix was identified using X-ray diffractometer and the surface of matrix suppositories after release test was examined by scanning electron microscopy. The sustained release of HC from these matrix suppositories was attributed to the network structure of EL.

• Bulletin of the Korean Chemical Society
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• 제24권2호
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• pp.209-218
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• 2003

Ecosystems in the Keweenaw Peninsula region of Lake Superior, USA, were disturbed by over 500 million tons of copper-rich mine tailings during the period 1850-1968. Metals leaching from these mine residues have had dramatic effects on the ecosystems. Vast acreages of exposed tailings that are over 100 years old remain unvegetated because of the combination of metal toxicity, absence of nutrients, and temperature and water stress. Therefore, it is important to characterize and fractionate solid copper phases for assessing labile forms of copper in soils and sediments contaminated by the mining wastes. X-ray diffraction analyses indicate that calcite, quartz, hematite, orthoclase, and sanidine minerals are present as major minerals, whereas cuprite,tenorite, malachite, and chalcopyrite might be present as copper minerals in the mining wastes. Sequential extraction technique revealed that carbonate and oxide fractions were the largest pools of copper (ca. 50-80%) in lakeshore and wetland stamp sands whereas the organic matter fraction was the largest reservoir (ca. 32%) in the lake sediments. The concentrations of iron and copper were inversely correlated in the oxide fraction suggesting that copper may occur as a surface coating on iron oxides. As particle size and water contents decrease, the percent of the copper bound to the labile carbonate fraction increases.

• Imaging Science in Dentistry
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• 제35권4호
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• pp.207-213
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• 2005

Purpose: To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods: The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results: Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd- T1W1. Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd- T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2Wl and Gd-T1W1. Conclusion: MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

• 한국재료학회지
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• 제18권6호
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• pp.289-293
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• 2008

Porous HAp with three-dimensional network channels was prepared in a polymer foam process using a in-situ formation. HAp/polyol with various HAp solid contents was formed with an addition of isocyanate. Under all conditions, the obtained porous HAp had pore sizes ranging $50\;{\mu}m$ to $250\;{\mu}m$. The influence of the HAp content on the physical and mechanical properties of porous HAp scaffolds was investigated. As the solid content increased, the porosity of the porous HAp decreased from 79.3% to 77.9%. On the other hand, the compressive strength of the porous HAp increased from 0.7 MPa to 3.7 MPa. With a HAp solid content of 15 g, the obtained porous HAp had physical properties that were more suitable for scaffolds compared to other conditions.

• Journal of Korean Society for Atmospheric Environment
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• 제22권E2호
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• pp.49-56
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• 2006

This pilot study focuses on emissions characterization of air pollutants produced from incineration of some municipal solid wastes (MSWs). The MSWs incinerated by an electric furnace maintained up to $600^{\circ}C$ included food, paper, and plastic wastes. The pollutants analyzed in this study included concentrations of volatile organic compounds (VOCs), bottom ash contents, and heavy metals extracted from the bottom ash of each waste. The VOCs identified were classified based on their chemical structure. The total emissions of VOCs produced from incineration of the papers were identified as the highest followed by those from the plastics and the food wastes. Aliphatic alkenes were major VOC compounds produced from incineration of plastic or food wastes, while furans were major VOCs produced from incineration of papers. The second major VOCs produced from incineration of food, plastics, and papers were aromatics. In particular, hazardous air pollutants such as benzene were produced with considerable amount of emission concentration. The bottom ash contents of papers were usually much higher than those of food or plastic wastes. The bottom ash contents produced from incineration of food and plastics were much lower than those of other MSWs. In analysis of heavy metals extracted by an ultrasonic method from the bottom ashes of the papers, high concentrations of heavy metals were identified from incineration of newspapers and box (cardboard). In addition, it was identified that the general public might be exposed to considerable amounts of lead concentrations during incineration processes and uses of paper cup and from ashes.

• 분석과학
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• 제16권2호
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• pp.125-133
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• 2003

적포도주에 들어 있는 trans-resveratrol을 분석하기 위하여 본 연구에서는 Sep-Pak $C_{18}$-cartridges를 이용한 고체상 추출법의 전처리 및 LC/MS-ESI 방법과 LC/MS-APCI 방법을 사용하여 국내에서 시판되고 있는 포도주에서 trans-resveratrol의 함량을 비교 분석하였다. LC/MS-ESI 방법에 의한 trans-resveratrol 함량은 $0.06-4.31{\mu}g/mL$로 검출되었고, 회수율은 88.4-97.9%, 상대 표준편차는 0.6-4.6%로 나타났으며, 검출한계는 $0.001{\mu}g/mL$이었다. LC/MS-APCI방법의 경우 trans-resveratrol 함량은 $0.09-4.02{\mu}g/mL$가 검출되었고, 검출한계는 $0.005{\mu}g/mL$로 나타났다.

• 한국식품영양과학회지
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• 제17권3호
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• pp.255-261
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• 1988

저염김치의 숙도조절과 가식기관의 연장을 목적으로 원료배추에 대하여 2%의 소금과 sodium malate buffer(SMB) 0.4%를 첨가하여 $20^{\circ}C$에서 숙성시키면서 pectin질의 변화를 조사하였다. SMB 첨가김치는 무첨가에 비하여 가식기간이 40시간 정도 연장되었고 맛 조직의 신선도 연화상태등에서 양호하였다. Alcohol insoluble solid(AIS)와 protopectin(PP)는 숙성에 따라 감소되었으며 SMB 첨가김치에서 감소율이 낮았고 pectic acid(PA)와 water soluble pectin(WSP)는 이와 반대로 숙성에 따라 증가되었는 데 증가율은 무첨가 김치에서 높았다. PP와 PA는 각각 hemicellulose로부터 유래된 hexose와 pentose를 함유하였으나 숙성 중에 감소하였고 감소율은 무첨가김치에서 높았다. 김치가 숙성됨에 따라 극성이 낮고 분자량이 극도로 높은 PP가 조직으로 용출되어 나온 반면 극성이 높은 저분자의 PP는 감소하는 경향을 나타내었는데 무첨가의 경우가 현저하였다.