• Title/Summary/Keyword: Preparation temperature

Search Result 2,374, Processing Time 0.035 seconds

Preparation of Traditional Malt-Sikhye - 2. Preparation by Malt (전통식혜제조-제 2보 엿기름에 의한 제조)

  • 안용근
    • The Korean Journal of Food And Nutrition
    • /
    • v.12 no.2
    • /
    • pp.170-176
    • /
    • 1999
  • Optimum preparation conditions of Korean traditional sweet rice drink 'malt-Sikye' were 1hour of rice soaking time 30min of malt extraction time 60$^{\circ}C$ of malt extraction tem-perature 60$^{\circ}C$ of saccharification temperature 1hour of agitation interval 5hour of saccharification time 5.5 of pH 4% of malt concentration and 20% of rice content. The malt-Sikhy contained to 17.1% of total sugar 11.2% of reducing sugar o.34mg/ml of protein and 4.7${\mu}$mol/ml of amino acid. The most abundant sugar found in malt-Sikhye was maltose. The commercial amylolytic enzymes were not effec-tive in preparation malt-Sikye.

  • PDF

Standardization of Recipe for the Preparation of Korean Foods (II) - For the focus on Chigae (Stew) - (한국음식의 조리법 표준화를 위한 연구(II) -찌개류 -)

  • 계승희;문현경;염초애;송태희;이성희
    • Korean journal of food and cookery science
    • /
    • v.11 no.3
    • /
    • pp.220-225
    • /
    • 1995
  • This study was attempted to standardize preparation methods of Korean foods; Chigae (Stew) such as Deonjang chigae (soybean stew) and Kimchi chigae (Kimchi stew). We followed cooking methods by using cookbooks, food service operation recipes, materials distributed by commercial food restaurants from their own experimental kitchens, and home recipes. Before this recipes were standardized, we thoroughly analyzed and modified them. The total yield and portions were determined together with material weights and procedures. And we evaluated food made by standardized recipes for acceptability, by taste panels from Sookmyung Women's University. It concluded that yield volune for doenjang chigae and kimchi chigae after cooking for 10 persons was 3 kg, optimum service temperature was 7$0^{\circ}C$, preparation time was 50 minutes, service volumes by one person was 300 g. This presentantion for the above on food materials and material weights, preparation methods as well as cautions and references are attached in this research paper.

  • PDF

Effect of Catalyst Preparation on the Selective Hydrogenation of Biphenol over Pd/C Catalysts

  • Cho, Hong-Baek;Park, Jai-Hyun;Hong, Bum-Eui;Park, Yeung-Ho
    • Bulletin of the Korean Chemical Society
    • /
    • v.29 no.2
    • /
    • pp.328-334
    • /
    • 2008
  • The effects of catalyst preparation on the reaction route and the mechanism of biphenol (BP) hydrogenation, which consists of a long series-reaction, were studied. Pd/C catalysts were prepared by incipient wetness method and precipitation and deposition method. The reaction behaviors of the prepared catalysts and a commercial catalyst along with the final product distributions were very different. The choice of the catalyst preparation conditions during precipitation and deposition including the temperature, pH, precursor addition rate, and reducing agent also had significant effects. The reaction behaviors of the catalysts were interpreted in terms of catalyst particle size, metal distribution, and support acidities.

Steam Reforming of Ethylene Glycol over Ni/Al2O3 Catalysts: Effect of the Preparation Method and Reduction Temperature (Ni/Al2O3 촉매를 사용한 에틸렌글리콜의 수증기 개질 반응: 촉매 제조 방법과 환원온도의 영향)

  • Choi, Dong Hyuck;Park, Jung Eun;Park, Eun Duck
    • Korean Chemical Engineering Research
    • /
    • v.53 no.3
    • /
    • pp.372-381
    • /
    • 2015
  • The effect of preparation method on the catalytic activities of the $Ni/Al_2O_3$ catalysts on steam reforming of ethylene glycol was investigated. The catalysts were prepared with various preparation methods such as an incipient wetness impregnation, wet impregnation, and coprecipitation method. In the case of coprecipitation method, various precipitants such as KOH, $K_2CO_3$, and $NH_4OH$ were compared. The prepared catalysts were characterized by using $N_2$ physisorption, inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, temperatureprogrammed reduction, pulsed $H_2$ chemisorption, temperature-programmed oxidation, scanning electron microscopy, and thermogravimetric analysis. Among the catalysts reduced at 773 K, the $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH or $K_2CO_3$ as precipitants showed the best catalytic performance. The preparation method affected the particle size of Ni, reducibility of nickel oxides, catalytic performance (activity and stability), and types of coke formed during the reaction. The $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH showed the increasing catalytic activity with an increase in the reduction temperature from 773 to 1173 K because of an increase in the reduction degree of Ni oxide species even though the particle size of Ni increased with increasing reduction temperature.

Influence of Temperature on the Electrolytic Oxidation of Sulphate Solutions by Electro-deposited Lead Peroxide Anode (전착과산화납양극에 의한 황산염. 전해산화시의 전해온도의 영향)

  • Chong Woo Nam;Hak Joon Kim
    • Journal of the Korean Chemical Society
    • /
    • v.15 no.5
    • /
    • pp.223-228
    • /
    • 1971
  • In the electrolytic preparation of persulphate from sulphate solution, the current efficiency decrease with temperature increase at the platinum anode. But in case of electrodeposited lead peroxide anode, the current efficiency increase with temperature of the solution. The reason seems to be that the ozone formation is faster in platinum anode than in lead peroxide as temperature increase.

  • PDF

Preparation and Properties of Pelletized Activated Carbons Using Coconut Char and Coal-Tar Pitch

  • Yang, Seung-Chun;Lee, Young-Seak;Kim, Jun-Ho;Lim, Chul-Kyu;Park, Young-Tae
    • Carbon letters
    • /
    • v.2 no.3_4
    • /
    • pp.176-181
    • /
    • 2001
  • A series of activated carbons were prepared from coconut shells and coal-tar pitch binder by physical activation with steam in this study. The effect of variable processes such as activation temperature, activation time and ratio of mixing was investigated for optimizing those preparation parameters. The activation processes were carried out continuously. The nitrogen adsorption isotherms at 77 K on pellet-shaped activated carbons show the same trend of Type I by IUPAC classification. The average pore sizes were about 19-21${\AA}$. The specific surface areas ($S_{BET}$) of pellet typed ACs increased with increasing the activation temperature and time. Specific surface area of AC treated for 90 min at temperature $900^{\circ}C$ was 1082 $m^2/g$. The methylene blue numbers continuously increased with increasing the activation temperature and time. On the other hand, iodine numbers highly increased till activation time of 60 min, but the rate of increase of iodine numbers decreased after that time. This indicates that new micropores were created and the existing micropores turned into mesopores and macropores because of increased reactivity of carbon surface and $H_2O$.

  • PDF

Wet Chemical Preparation of Li-rich LiMn$_2$O$_4$ Spinel by Oxalate Precipitation (Oxalate 침전을 이용한 Li-과량 LiMn$_2$O$_4$ Spinel의 습식합성가 분말 특성)

  • 이병우;김세호
    • Journal of the Korean Ceramic Society
    • /
    • v.36 no.7
    • /
    • pp.698-704
    • /
    • 1999
  • Li rich Li1+xMn2-xO4(x=0.07) spinel powders were prepared by an oxalate precipitation of wet chemical methods at temperature lower than $600^{\circ}C$. The FTIR results showed that the powders prepared at $600^{\circ}C$ had high degree of crystal quality comparing with the spinel powders prepared by solid state reaction at 75$0^{\circ}C$ which was the lowest synthesis temperature of the solid state reaction method. The particle size of powders prepared by the oxalate precipitation at $600^{\circ}C$ was smaller than 0.2${\mu}{\textrm}{m}$ and the specific surface area was 11.01 m2/g A heat treatment over 90$0^{\circ}C$ formed second phase in the precipitates. It was shown that there were phase transitions at temperatures. T1,T2 and T2. The transitions involved weight loss and gain during heating and cooling. The low temperature synthesis below $600^{\circ}C$ avoided the second phase formation and the prepared powders showed improved compositional and physical properties for secondary lithium battery applications.

  • PDF

Preparation of Perovskite Catalysts and Its Application to Methane Combustion (페롭스카이트 촉매의 제조와 메탄 산화에 응용)

  • Hahm, Hyun-Sik;Kim, Kyu-Sung;Ahn, Sung-Hwan;Shin, Ki-Seok;Kim, Song-Hyoung;Park, Hong-Soo
    • Journal of the Korean Applied Science and Technology
    • /
    • v.24 no.1
    • /
    • pp.67-73
    • /
    • 2007
  • Methane combustion over perovskite catalysts was investigated. For the preparation of catalysts, Co, Mn, Fe, and Ni were used as B-site components of the perovskite catalysts $(ABO_3)$ and La was used as A-site component. The effect of calcination temperature on methane combustion and perovskite structure was also investigated. The structure of perovskites, surface area, and adsorbed oxygen species were tested with XRD, BET apparatus, and $O_2-TPD$, respectively. The formation of perovskite structure was affected by the calcination temperature. The catalyst desorbing oxygen at a lower temperature showed better activity for the methane combustion, therefore, the oxygen species desorbing at lower temperatures is responsible for the methane combustion.

A Study on Electrode Preparation for Alkaline Fuel Cell (알칼리 연료전지 전극제조에 관한 연구)

  • Hong, Jin Ki;Lee, Kyung Ju;Lee, Wha Young
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.2 no.1
    • /
    • pp.57-67
    • /
    • 1990
  • This study is proposed to investigate the effect of electrode preparation method for Alkaline Fuel Cell using NaOH as an electrolyte on the Fuel Cell performance. The materials used for the preparation of electrode are Pt and Ag on Vulcan XC-72. Surface area of Vulcan XC-72 have different values according to the pretreatment conditions and the dispersion of Pt is dependent on the impregnation Particle size of Pt impregnated on unpretreated carbon was observed to be $20{\sim}40{\AA}$ and that on pretreated carbon in $N_2$ stream at $950^{\circ}C$ was found to be finely dispersed less then $15{\AA}$. The electrode performance was affected by the particle size of metals and operating temperature. It was revealed from this study that the optimum particle size about $30{\AA}$ and optimum temperature range is between $90{\sim}100^{\circ}C$.

  • PDF

Development of EM Wave Absorbers for GHz Frequency (GHz 대역용 전파흡수체의 개발)

  • 문상현;신승재;김동일;송재만;최정현;김기만
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2004.04a
    • /
    • pp.17-22
    • /
    • 2004
  • We prepared EM wave absorbers by using recycled Ba and Sr ferrites for GHz frequency, and investigated the effects of carbon additions, thickness and preparation temperatures on their EM wave absorption properties. We clarified that it is very important to consider carbon amounts in Ba and Sr ferrites and preparation temperature for Ba and Sr ferrite EM wave absorbers with high quality. In this study, the developed a EM Wave absorber satisfying over 20 dB.

  • PDF