• 한국식품과학회지
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• 제22권6호
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• pp.707-710
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• 1990

김치의 산업화를 기초연구의 일환으로 김치를 제조할 때 작업장의 온도조절과 제품의 염농도가 저장성에 미치는 효과를 검토하였다. 김치를 대규모로 제조시 작업장의 온도는 $25^{\circ}C$보다 $15^{\circ}C$에서 작업하는 것이 김치저장에 효과적이었으며 염의 농도는 3%가 저장성 향상에 효과적이었다. 이들 조건에서 저장온도는 $-1{\pm}1^{\circ}C$가 바람직하여 120일까지 상품성을 유지하였고 $-5^{\circ}C$에서는 동결되는 현상을 보였다. 포장시기는 발효전 포장이 김치의 품위유지에 바람직하였다.

• 한국수소및신에너지학회논문집
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• 제24권6호
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• pp.550-557
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• 2013

A glucose hydrothermal method is described for preparing hollow carbon spheres (HCS), which have a regular morphology and a high Brunauer-Emmett-Teller surface area of 28.6 m2/g. Scanning electron microscopy shows that they have thin shells and diameter between 2 and 8 ${\mu}m$. The HCSs were modified for the enhanced room temperature hydrogen storage by employing Ni nanoparticles on their surface. The Ni-decorated HCSs were characterized by X-ray diffraction, transmission electron microscopy coupled with an energy dispersive spectroscope, and an inductively coupled plasma spectrometer, indicating that fine and well-distributed Ni nanoparticles can be accomplished on the HCSs. The hydrogen uptake capacity in HCSs with and without Ni loading was evaluated using a high-pressure microbalance at room temperature under a hydrogen pressure upto 9 MPa. As much as 1.23wt.% of hydrogen can be stored when uniformly distributed Ni nanoparticles are formed on the HCSs, while the hydrogen uptake capacity of as-received HCSs was 0.41 wt.%. For Ni nanoparticle-loaded HCSs, hydrogen molecules could be easily dissociated into atomic hydrogen and then chemically adsorbed by the sorbents, leading to an enhanced capacity for storing hydrogen.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1301-1302
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• 2006

Sintered composites of Al-8wt%Cu-10vol%SiCp were deformed by repressing or equal channel angular pressing(ECAP) at room temperature, $500^{\circ}C$ and $600^{\circ}C$. Repressing produced more densification than ECAP but resulted in much lower transverse rupture strengths. In both cases, deformation at room temperature and $500^{\circ}C$, resulted in much lower strengths than deformation at $600^{\circ}C$, and also caused the fracturing of some SiC particles. The higher bend strengths and less SiC fracturing at $600^{\circ}C$ are attributable to the presence of an Al-Cu liquid phase during deformation. The employment of copper coated SiC instead of bare SiC particles for preparing the composites was found not improving the properties.

• 전기의세계
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• 제23권6호
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• pp.49-55
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• 1974

Amorphous semiconductor from As 30 Te 48 Ge 10 Si 12 was prepared, and studied electron microscopy, X-ray analysis and resistivity measurement. It's resistivity is 1.56*10$^{6}$ .ohm.-cm when small ampule is used for preparing sample it is found that no phase separation has occurced by electron microscopy, and that phase transition temperature is 232.deg. C by differential Thermal Analysis. The specimen showed threshold switching that the low resistance state occur at critical electric field and the resistance recover at low applied field. Critical electric field of the switching is 10$^{5}$ V/cm at room temperature. Threshold voltage secreace exponentially with increasing ambient temperature and at that each voltage resistance of the switching device increase exponentially. According to the series resistance and applied vottage current slope on the V-I curve is varied. When applied voltage is decreased after switching, the resistance of the switching device is increased. By this result the origin of the switching is the Joule's heating.

• 한국지반환경공학회 논문집
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• 제17권10호
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• pp.5-11
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• 2016

본 연구에서는 포름알데히드를 상온산화시켜 제거하는 $Pt/TiO_2$ 촉매의 상용화 인자들이 조사되었다. 활성 귀금속 함량 최적화를 위해 촉매의 백금(Pt) 담지량을 변화시켜 제조 후 성능을 평가하였으며, 그 결과 1wt% 함량이 가장 이상적인 함량임을 확인하였다. 또한 활성금속인 Pt를 환원하여 제조한 환원 촉매가 상온에서 우수한 포름알데히드 산화 능력을 나타내었다. 이를 통해 활성금속의 산화가에 따라 성능이 변화될 수 있으며, 백금의 경우 metallic Pt($Pt^0$)로 존재할수록 포름알데히드 상온산화 성능이 증진될 수 있음을 확인하였다. 촉매의 운전인자를 도출하기 위한 공간속도 영향 평가 결과 공간속도가 낮을수록 촉매량 증가에 의해 포름알데히드 전환율이 증진되는 결과를 나타내었다. 또한 공기 내 반드시 존재하는 물질인 수분의 공기 내 공존 시 영향 평가를 실시하였으며, 그 결과 수분이 공존할 때 포름알데히드 산화반응이 수분이 존재하지 않은 조건에서의 활성보다 증진되었다. 상기 결과들을 통해 어떤 추가 에너지원 없이도 포름알데히드를 제거 할 수 있는 상온산화 촉매 상용화를 위한 핵심인자들을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.329.1-329.1
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• 2014

In this paper, we report electrical, optical and structural properties of Al-doped zinc oxide (AZO) thin films deposited at different substrate temperatures and pressures. The films were prepared by radio frequency (RF) magnetron sputtering on glass substrates in argon (Ar) ambient. The X-ray diffraction analysis showed that the AZO films deposited at room temperature (RT) and 20 Pa were mostly oriented along a-axis with preferred orientation along (100) direction. There was an improvement in resistivity ($3.7{\times}10^{-3}{\Omega}-cm$) transmittance (95%) at constant substrate temperature (RT) and working pressure (20 Pa) using the Hall-effect measurement system and UV-vis spectroscopy, respectively. Our results have promising applications in low-cost transparent electronics, such as the thin-film solar cells and thin-film transistors due to favourable deposition conditions. Furthermore our film deposition method offers a procedure for preparing highly oriented (100) AZO films.

• 한국물환경학회지
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• 제27권3호
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• pp.286-292
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• 2011

Preparing for the Standards for Effluents which will be strengthen from 2012, many ways like remodellings and repairs of sewage treatment plant (STP) are considered. The treatment of the recycle water from the sludge treatment process contains high-strength organic compounds and nitrogen is considered as alternative. In the treatment of high-strength nitrogen, nitritation has more economic advantages than nitrification. In this study, lab-scale reactor was operated at the $35^{\circ}C$, $20^{\circ}C$ and $10^{\circ}C$ conditions using effluent of anaerobic digester to investigate the nitrogen removal by nitritation. Long-term stable nitritation was achieved at the $35^{\circ}C$, $20^{\circ}C$ but $10^{\circ}C$. In the stable nitritation states, nitrite conversion was higher at the high temperature of $35^{\circ}C$ than the room temperature of $20^{\circ}C$. Also shorter solid retention time (SRT) was needed to induce high nitrite conversion at the high temperature of $35^{\circ}C$. It was showed that temperature and SRT are important factors to induce nitritation.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.169-169
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• 2016

In this paper, we report electrical, optical and structural properties of Al-doped zinc oxide (AZO) thin films deposited at different substrate temperatures and pressures. The films were prepared by radio frequency (RF) magnetron sputtering on glass substrates in argon (Ar) ambient. The X-ray diffraction analysis showed that the AZO films deposited at room temperature (RT) and 20 Pa were mostly oriented along a-axis with preferred orientation along (100) direction. There was an improvement in resistivity ($3.7{\times}10^{-3}{\Omega}-cm$) transmittance (95%) at constant substrate temperature (RT) and working pressure (20 Pa) using the Hall-effect measurement system and UV-vis spectroscopy, respectively. Our results have promising applications in low-cost transparent electronics, such as the thin-film solar cells and thin-film transistors due to favourable deposition conditions. Furthermore our film deposition method offers a procedure for preparing highly oriented (100) AZO films.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2010년도 춘계학술 발표회
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• pp.199-199
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• 2010

Polymeric membranes have been widely used to separate gas mixtures, such as $O_2/N_2,\;CO_2/CH_4,\;CO_2/N_2$, and olefin/paraffin. The permeation selectivity is the ratio between composition ratio at the permeate side and composition ratio at the feed side. In addition, the permeation selectivity is a product of solubility selectivity and diffusivity selectivity. We present a novel idea and describe its experimental result, which was achieved by preparing polymer gel films that included a room temperature ionic liquid (RTIL) in a polymer matrix. It is known that $CO_2$ can dissolve easily in imidazolium-based RTILs. We prepared polymer-ionic liquid gel films using an ionic liquid, 1-ethyl-3-methylimidazolium acetate ([emim] acetate, C-tri) and a host polymer, poly (vinyl acetate) (PVAc, Aldrich).

• Journal of Pharmaceutical Investigation
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• 제15권2호
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• pp.83-90
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• 1985

The effects and the optimum manufacturing conditions for the preparation of synthetic aluminum silicate which has acid-consuming power and adsorbing capacity were investigated. The results are as follows: 1. The adsorbing capacity was affected by the mixing order of the reactants, that is, the excellent ones were obtained by the method which add the sodium silicate solution to the potassium alum solution. 2. Even though preparing by the bane manufacturing condition, the acid-consuming power is superior to the adsorbing capacity. 3. According to the Box-Wilson Plan, the optimum reaction conditions are concentration of sodium silicate solution; 38% w/w, settling time; 43 hours at room temperature, drying time; 13 hours at $110^{\circ}C$.