• Preventive Nutrition and Food Science
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• 제6권2호
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• pp.112-116
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• 2001

Oxidized potato starch/polyethylene (PE) cast films were prepared with different percentages of linear low density PE (LLDPE), oxidized potato starch and prooxidant. For the determination of biodegradability of the films, lignocellulose-degrading Streptomyces viridosporus T7A (ATCC 39115) was used. Films were chemically disinfected and incubated with S. viridosporus by shaking at 100 rpm at 37$^{\circ}C$ for eight weeks. Hydroxyl indices of the films by Fourier-Transform Infrared Spectroscopy, mechanical Properties of the films by Instron and film morphology by scanning electron microscope (SEM) were measured. The hydroxyl index of the film containing the oxidized potato starch incubated with S. viridosporus T7A was higher than that of the corresponding control. All the films containing 5% and 10% oxidized starch showed a decrease of tensile strength on the films after incubation when the corresponding uninoculated film was compared. In the oxidized starch/PE film incubated with S. viridosporus T7A, partial destruction of starch and PE was examined by SEM.

• 펄프종이기술
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• 제30권3호
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• pp.15-21
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• 1998

Crude enzymes of Trichoderma viride and Phanerochaete chrysosporium were evaluated for their effect to brightness and physical properties of recycled pulp from newspaper and corrugated container board. The brightness of recycled pulp from newspaper increased with crude enzymes from Trichoderma viride and Phanerochaete chrysosporium. The brightness of recycled pulp of corrugated container board increased with crude enzyme from Phanerochaete chrysosporium, but decreased with crude enzyme from Trichoderma viride. The Δbrightness with chemical bleaching of crude enzyme treated pulp was lower than that of heat killed enzyme treated pulp, but the final brightness of pulp was increased. Modification of recycled paper with crude enzymes can result in a substantial increase in physical properties with little no loss in pulp freeness.

• 한국레이저가공학회지
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• 제11권4호
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• pp.1-6
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• 2008

This paper describes microscale laser structuring of electrospun(ES) PCL and PET nanofiber meshes. Electrospinning produces non-woven meshes of synthetic or natural materials fibers with diameters ranging from micron down to the nanometer scales that are advantageous for the supporting the growth of the small scale structures. Ultrashort laser found to be effective on the fabrication of engineeredtissue scaffold with minimum heat affect and ultra precision ablation patterns. The affect of energy range for ablation quality was analyzed and ablation characteristics of PCL and PET were compared.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 춘계 총회 및 학술발표회
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• pp.136-139
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• 2004

The dyeing effluent is a highly colored stream containing unfixed dyes along with salts and auxiliary chemicals such as emulsifying agents. Moreover, Textile dying is a chemically intensive process and consumes large quantities of water. Difficulties in the effluent treatment arise from its non-degradable property by aerobic digestion.(omitted)

• 한국재료학회지
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• 제18권8호
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• pp.432-437
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• 2008

Titanium oxide films and powders are attached onto carbon cloths via RF reactive sputtering and an epoxy resin mixture, respectively. $TiO_2$/carbon composite materials were used to investigate the photoelectrochemical degradation of perchlorate ions in water. The energy band gaps of the RF-sputtered $TiO_2$ thin films ranged from 3.35-3.44 eV. A photocurrent of the powdered $TiO_2$ as illuminated by ultra-violet light for 30 min. was $2.79\;mA/cm^2$. Perchlorate ions in water were shown to be degradable by a UV-illuminated $TiO_2$ powder/carbon/Nafion/carbon composite.

• 한국환경보건학회지
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• 제36권3호
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• pp.222-228
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• 2010

Biological degradation of nitrogen-containing aromatic compounds was investigated in activated sludge previously adapted to mineralize low concentrations of nitrogen-containing aromatic compounds. Normally, the time required for 95% degradation of 10 mg/l dinitrophenol (DNP) under aerobic conditions was less than 4 hours without any lag, and with mixed liquor suspended solid (MLSS) levels from 600 to 1,000 mg/l. However, when the initial DNP concentration was increased to 75 mg/l, lags and even complete inhibition of DNP degradation were observed. The length of the lag was found to increase proportionally with decreasing MLSS levels. When dilute activated sludge was incubated for extended periods (192 hours), degradation of 75 mg/l DNP did eventually occur after lag periods of 37 to 144 hours, depending on the MLSS concentration. DNP was degradable in high concentrations if MLSS concentrations were sufficiently high to allow growth of bacteria resistant to the toxic effects of DNP.

• Bulletin of the Korean Chemical Society
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• 제28권1호
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• pp.63-67
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• 2007

Biodegradable cationic poly(ester-amide) polymers were synthesized by double-monomer method, that showed excellent solubility in many organic solvents and water. Different degradation patterns were obtained by the regulation of monomer ratios and overall long period of time of DNA protection up to 12 days was shown by PicoGreen reagent assay. Good transfection profiles in the presence of serum and very low toxicity on mammalian cells may allow these polymers to become suitable for long-term gene delivery systems and therapeutic applications.

• 도시과학
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• 제8권2호
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• pp.19-23
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• 2019

With the continuous progress of modern science and technology and the rapid development of economy, with the continuous development of society, the treatment of industrial and domestic sewage has become a hot concern. Toxic substances and non-degradable pollutants in wastewater also have a great impact on the environment. This paper mainly expounds the current environmental situation and the adsorption mechanism of activated carbon. And the application and development of activated carbon adsorption in wastewater.

• ETRI Journal
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• 제8권3호
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• pp.29-43
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• 1986

어떤 고장이 시스팀의 기능을 완전히 마비시키는 것이 아니라 그 성능이 저하된 상태에서 운용할 수 있는 degradable system에서는 고전적인 신뢰도 모형을 적용하기가 어려우며, 여기서 성능과 신뢰도는 매우 밀접한 관련이 있다. 본고에서는 성능신뢰도(Performance reliability)에 대한 개념 및 모형화 방법에 대해 살펴보고 실제로 TDX-1의스위치 네트워크인 SWCD의 성능을 해석하여 성능신뢰도를 구하였다. SWCD의 성능척도인 통화성공률에 영향을 미치는 요인으로는 스위치 네트워크 내에서의 blocking, T-SW 및 S-SW의 고장, 그리고 T-SW 및 S-SW의 고장으로 인해 DLC 와 TLC의 가용한 서비스 채널이 감소함으로써 발생하는 DLC 및 TLC에서의 blocking등을 들 수 있는데 이 요인들을 고려하여 SWCD의 성능을 해석하였으며, SWCD에 요구되는 표준성능(Normalized performance) 이 0.99라 할 때 single unit라고 가정한 경우 SWCD의 성능 신뢰도는 MTUO(Mean Time to Unreliable Operation)가 3076.7시간이었다. 또한 성능을 해석하는 과정에서 디지틀 스위치 네트워크인 SWC만의 최대 발신 통화처리 용량을 구한 결과, 스위치 네트워크 내에서의 blocking 확률에 대한 최대 허용치를 $10^-3$으로 하였을 때 약 1,700Erlang이었다.

• 대한화학회지
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• 제60권4호
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• pp.257-260
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• 2016

A new perfluorobutyl substituted cyclic type disodium alkanesulfonate is designed, synthesized and characterized as alternative substance to perfluorooctane sulfonic acid (PFOS, 1), a well-known surfactant. Cylic type sulfonate was accomplished from commercially available 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol in four steps. Bio-degradable perfluorobutyl moiety was introduced from fluorous diol, which is symmetrically substituted amphiphile via installation of an intermediate trifluoromethanesulfonyl ester and easily manipulated by double displacement of triflate using potassium malonate and further reduction followed by nucleophilic ring opening are key reactions to get target disodium alkanesulfonate. The efficiency and simplicity in the synthesis of this material offer a new strategy to design PFOS alternatives.