• Title/Summary/Keyword: preparing room temperature

Search Result 43, Processing Time 0.031 seconds

Effect of Temperature and Salts Concentration of Kimchi Manufacturing on Storage (김치제조시의 온도 및 염농도에 따른 저장효과)

  • Choi, Shin-Yang;Kim, Young-Boong;Yoo, Jin-Young;Lee, In-Sun;Chung, Kun-Sub;Koo, Young-Jo
    • Korean Journal of Food Science and Technology
    • /
    • v.22 no.6
    • /
    • pp.707-710
    • /
    • 1990
  • To extend the shelf-life of kimchi, effective temperature in preparing room and salts concentration of product were monitored. The temperature in preparing room was excellent at $15^{\circ}C$ than $25^{\circ}C$ and effective salt concentration was 3.0% for storage. Under the these conditions, preservation temperature was desirable at $-1{\pm}1^{\circ}C$ and can be stored over 120 days. When the storaging temperature was $-5^{\circ}C$, it showed to freeze the tissue and juice of kimchi. The advisable packing time for storage was just after mixing.

  • PDF

Ni Nanoparticles-hollow Carbon Spheres Hybrids for Their Enhanced Room Temperature Hydrogen Storage Performance

  • Kim, Jin-Ho;Han, Kyu-Sung
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.24 no.6
    • /
    • pp.550-557
    • /
    • 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.

Effect of Post Deformation on the Structure and Properties of Sintered Al-Cu-SiC Composites

  • Chung, Hyung-Sik;Heo, Ryun-Min;Kim, Moon-Tae;Ahn, Jae-Hwan
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09b
    • /
    • pp.1301-1302
    • /
    • 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.

  • PDF

A study of the effect of the temperature on the As Te Ge Si amorphous semiconductor (As Te Ge Si 무정형 반도체의 온도영향)

  • 박창엽
    • 전기의세계
    • /
    • v.23 no.6
    • /
    • pp.49-55
    • /
    • 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.

  • PDF

A Study on the Optimization of Process Operation & Catalyst Preparing for Commercialization of Formaldehyde Room Temperature Oxidation Catalyst (포름알데히드 상온산화 촉매의 상용화를 위한 촉매 제조 및 공정 운전조건 최적화 연구)

  • Lee, Sanghyun;Park, Inchul;Kim, Sungsu
    • Journal of the Korean GEO-environmental Society
    • /
    • v.17 no.10
    • /
    • pp.5-11
    • /
    • 2016
  • In this study, the factors affecting commercialization of $Pt/TiO_2$ catalyst, which can oxidize HCHO at room temperature, was investigated. In order to determine the optimum noble metal loading, the catalytic activity was evaluated by varying the Pt loadings; the best catalytic activity was achieved for 1 wt% of Pt. In addition, the catalyst prepared under the reduction condition showed an excellent HCHO oxidation conversion at room temperature. Based on these results, it was confirmed that the activity could be changed by oxidation state of active metal, and in case of Pt, metallic Pt ($Pt^0$) species was more active on HCHO oxidation at room temperature. As a result of evaluating an effect of space velocity to determine the optimum operating condition, it was found that in the lower space velocity, conversion rate of HCHO was increased due to increase of catalyst bed. Catalytic activity was greater in the presence of moisture than in its absence. Through above results, the key factors for commercialization of oxidation catalyst, which was operated at room temperature even without any additional energy source was confirmed.

Structural and Electrical Properties of a-axis ZnO:Al Thin Films Grown by RF Magnetron Sputtering

  • Bong, Seong-Jae;Kim, Seon-Bo;An, Si-Hyeon;Park, Hyeong-Sik;Lee, Jun-Sin
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.329.1-329.1
    • /
    • 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.

  • PDF

Effect of Temperature on Nitritation using Effluent of Anaerobic Digester (혐기 소화조 유출수의 아질산화 반응에 온도가 미치는 영향)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Korean Society on Water Environment
    • /
    • v.27 no.3
    • /
    • pp.286-292
    • /
    • 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.

Effect of Pressure and Temperature on Al-doped Zinc Oxide Thin Films Deposited by Radio Frequency Magnetron Sputtering

  • Kang, Junyoung;Park, Hyeongsik;Yi, Junsin
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2016.02a
    • /
    • pp.169-169
    • /
    • 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.

  • PDF

Poly (vinyl acetate)-Ionic Liquids Membranes for $CO_2$ Capture (이산화탄소 포집용 폴리비닐아세테이트-이온성액체 막)

  • Lee, Sang-Jin;Choe, Su-Hyeon;Baek, Il-Hyeon
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
    • /
    • 2010.04a
    • /
    • pp.199-199
    • /
    • 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).

  • PDF

Effects of Several Manufacturing Conditions on Acid Consuming and Adsorbing Capacities of Aluminum Silicate (합성규산(合成珪酸)알루미늄의 제산능(制散能) 및 흡착능(吸着能)에 미치는 제조조건(製造條件)의 영향(影響))

  • Lah, Woon-Lyong
    • Journal of Pharmaceutical Investigation
    • /
    • v.15 no.2
    • /
    • pp.83-90
    • /
    • 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 $110^{\circ}C$.

  • PDF