• 자원리싸이클링
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• 제17권3호
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• pp.21-28
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• 2008

자동차 부품으로 사용되는 air filter media인 PET와 frame으로 사용되는 PP의 혼합폐플라스틱의 제조공정의 edge scrap 및 부품의 교체로 발생된 post-consumer waste에 대한 재활용 연구를 진행하였다. 수거된 혼합 폐플라스틱을 파쇄 및 건조시킨 후 세 가지 형태의 상용화제의 배합비 별로 압출기를 이용한 용융 블렌딩을 실시하여 재생 칩을 제조하였다. 사용된 상용화제는 EVA, MBS, 그리고 가소화 재생 PVB이고, 이들의 배합비는 $3{\sim}10wt.%$까지 혼합하였다. 상용화제의 종류와 배합비의 변화에 따른 기계적 특성과 열적 특성을 비교하였다. 이들 상용화제 종류별 분석에서는 MBS 상용화제가 가장 뛰어난 기계적 특성을 좌였고, 배합비는 $3{\sim}5wt.%$에서 우수한 특성 값들을 보였다. 또한 EVA를 상용화제로 사용한 경우 배합비가 $3{\sim}5wt.%$에서 내충격성 및 열적 특성의 향상을 보여 내충격성이 요구되는 재활용 제품으로의 응용이 기대된다. 재생 PVB수지를 상용화제로 사용한 경우는 전체적으로 특성치의 저하를 보이기는 하나 toughening effect가 요구되는 분야로의 응용이 기대된다.

• Journal of the Korean Wood Science and Technology
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• 제52권5호
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• pp.504-523
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• 2024

Timber industry waste is being examined for cellulose manufacturing to give important benefits. The study's goal is to investigate the properties of cellulose powder derived from sawdust waste after it has been reinforced with ferrous-ferric oxide nanoparticles (Fe₃O₄-NPs). Sawdust cellulose powder was produced from Sengon (Albizia chinensis) wood waste in this study. The crushed sawdust waste is handled with alkalization and bleaching. Cellulose powder is then reinforced with Fe₃O₄-NPs at 10 wt.%, 20 wt.%, and 30 wt.%. The magnetic cellulose powder was analysed by X-ray diffraction, Fourier Transform Infrared, scanning electron microscopy morphology, magnetic vibrating sample magnetometer, Brunauer-Emmett teller, and adsorption tests for Methylene Blue and Congo Red dyes. Structure study identifies sawdust as cellulose 1β, with peaks at 14°, 16°, and 22° diffraction angles. The addition of Fe₃O₄-NPs reduces the crystalline index of sawdust cellulose powder from 68.50% to 63.38%, and functional group bond analysis revealed many peak shifts indicating a change in the chemical bonds of magnetic cellulose powder. Incorporating Fe₃O₄-NPs into sawdust cellulose powder confers magnetic and superparamagnetic properties to the sawdust cellulose. Similarly, the surface texture of magnetic cellulose seems rougher as the surface area increases. These parameters imply a 31.8% increase in Congo Red adsorption, using adsorption kinetics based on the pseudo-first-order model.

• 보건행정학회지
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• 제29권3호
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• pp.248-261
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• 2019

Establishing a healthcare delivery system is key to building a cost-effective healthcare system that can prevent the waste of healthcare resources and increase efficiency. Recently, the rapid increase in the national medical expenditures due to the aging of the population and the increase in chronic diseases has raised the question about the sustainability of the healthcare system including the health insurance system. This is why we need to reform the medical delivery system, including the function setting of medical institutions. Accordingly, gradual and practical efforts based on the recognition of reality are needed for solving the problems and improving the medical delivery system. The first effort is to secure policy measures to establish functions and roles of medical institutions which are the basis of the healthcare delivery system, and a systematic medical use system for appropriate medical use. This approach can be achieved through a reasonable health insurance schemes. Without reasonable reform efforts, it will be difficult for Korea's health care system to develop into a system that can provide cost-effective and high-quality medical services that the people want.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.219-230
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• 2018

The present study examined a moving bed biofilm reactor (MBBR) bioreactor on a laboratory scale for simultaneous removal of atrazine, organic carbon, and nutrients from wastewater. The maximum removal efficiency of atrazine, chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN) were 83.57%, 90.36%, 90.74% and 87.93 respectively. Increasing salinity up to 40 g/L NaCl in influent flow could inhibit atrazine biodegradation process strongly in the MBBR reactor.Results showed that MBBR is so suitable process for efficiently biodegrading of atrazine and nitrogen removal process was based on the simultaneous nitrification-denitrification (SND) process.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2004년도 Sharing Experience of Human and Ecological Risk Assessment and Management in Asia/Pacific Region
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• pp.92-92
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• 2004

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 2000년도 제52차 추계학술대회 연제집
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• pp.290-291
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• 2000

• 생명과학회지
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• 제15권3호
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• pp.337-343
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• 2005

주정공장에서 배출되는 타피오카 주정증류 폐기물을 발효기질로 하여 플라스크 진탕배양기에서 A. niger균주를 이용하여 폐기물 처리 및 구연산을 생산하는 실험에서 다음과 같은 결과를 얻었다. A. niger ATCC 9142균주를 사용하여 배양온도를 $25^{\circ}C\;30^{\circ}C 및 $35^{\circ}C$로 변화하여 발효하였을 때 구연산 농도는 $30^{\circ}C$에서 6.09g/1로 최대가 되었으며, 플라스크 진탕배양기의 배양온도를 $30^{\circ}C$로 유지하면서 초기 pH를 조절하여 발효를 행한 결과, pH 4.3인 원폐수에서 구연산 생성량이 6.37g/l로 가장 높았다. 질소원, 인산원 및 금속이온이 구연산 생성에 미치는 영향을 알아보기 위하여 $NH_4NO_3,\;KH_2PO_4$ 및 $Mn^{2+}$를 첨가한 결과 이들 첨가물들이 구연산 생산을 감소시켰고, methanol, ethanol, isopropanol 및 n-propanol의 첨가가 구연산 발효에 미치는 영향을 알아보기 위한 실험에서는 methanol과 ethanol의 첨가가 구연산 생성을 촉진시켰다.

• 한국융합학회논문지
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• 제12권6호
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• pp.33-38
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• 2021

경량의 의료방사선 차폐시트를 제작하기 위해 새로운 차폐소재를 검토하였다. 가정에서 음식물 쓰레기로 버려지는 계란 껍데기 분말을 고분자 물질과 혼합하여 차폐재료의 가능성을 검증하고자 하였다. 기존의 경량 소재는 친환경의 조건을 만족하지만 주 재료 정제과정의 비용으로 인해 차폐시트 제작의 경제성에 어려움이 있다. 본 연구는 가정용 폐기물인 계란 껍데기를 이용하여 이러한 문제점을 해결하고자 한다. 고분자 물질인 HDPE를 이용하여 3 mm 두께의 차폐시트를 제작하였으며, 차폐시트 단면 내의 입자 분포상태도 분석하였다. 입자의 모양은 대체로 거칠게 구성되어 입자 간 공극이 있었으며, 단위 면적당 무게는 평균 1.5 g/cm² 로 나타났다. 차폐성능은 저에너지 영역에서는 20%대, 고에너지 영역에서는 10%대의 차폐성능을 보여 저선량 의료방사선 차폐시트의 재료로 가능성을 보여주었다.

• 한국식품저장유통학회지
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• 제31권1호
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• pp.1-14
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• 2024

The utilization of coatings composed of bio-based materials in the processing and preservation of meat presents an environmentally conscious, secure, cost-effective, and superior method for prolonging the storage life of meat while also preserving its nutritional value. In this study, changes in physical, chemical, and microbiological characteristics of freshly cut beef coated with distilled water (control) and keratin-starch composites (K-S) functionalized with 0.0-, 0.2-, 0.6-, and 1.0-mL avocado peel polyphenolic-rich extract (APPPE) kept at 4℃ for 12 days were evaluated periodically at 3-day interval using standard techniques. Keratin was extracted from waste feathers, while starch was obtained from ginger rhizomes. Following a 12-day storage period, beef coated with APPPE-enriched K-S composites exhibited a significant (p<0.05) improvement in shelf life by minimizing deteriorative changes in pH and color (as determined by metmyoglobin level) in addition to inhibiting oxidative changes in lipids (as determined by TBARS level) and proteins (protein carbonyl level) in comparison to control and K-S composite without APPPE. Furthermore, microbial growth was significantly (p<0.05) suppressed in meat coated with K-S composite functionalized with APE at 0.6 and 1.0 mL compared to the control. The study suggested that APPPE-enriched K-S composite could offer an eco-friendly and safe food preservation technique for fresh meat.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.278.2-278.2
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• 2003

A column-switching semi-micro HPLC method with fluorescence detection was developed for the direct analysis of rebamipide in human plasma. Plasma was filtered through a 0.45 $\mu\textrm{m}$ membrane filter and 5 ${\mu}\ell$ of the filtrate was directly injected onto the pre-column. After elution of the plasma proteins to waste, the retained rebamipide and internal standard(ofloxacin) were transferred to a C18 semi-microcolumn (5$\mu\textrm{m}$, 150 ${\times}$2.0mm) where they were separated using acetonitrile-1.4％ acetic acid (40:60, v/v) as mobile phase. (omitted)