• Title/Summary/Keyword: soaking temperature.

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Optimization of soaking in aqueous ammonia pretreatment of canola residues for sugar production (당 생산을 위한 카놀라 부산물의 암모니아 침지 전처리 공정의 최적화)

  • Yoo, Hah-Young;Kim, Sung Bong;Lee, Sang Jun;Lee, Ja Hyun;Suh, Young Joon;Kim, Seung Wook
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.114.1-114.1
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    • 2011
  • Bioenergy production from lignocellulosic biomass and agriculture wastes have been attracted because of its sustainable and non-edible source. Especially, canola is considered as one of the best feedstock for renewable fuel production. Oil extracted canola and its agriculture residues are reuseable for bioethanol production. However, a pretreatment step is required before enzymatic hydrolysis to disrupt recalcitrant lignocellulosic matrix. To increase the sugar conversion, more efficient pretreatment process was necessary for removal of saccharification barriers such as lignin. Alkaline pretreatment makes the lignocellulose swollen through solvation and induces more porous structure for enzyme access. In our previous work, aqueous ammonia (1~20%) was utilized for alkaline reagent to increase the crystallinity of canola residues pretreatment. In this study, significant factors for efficient soaking in aqueous ammonia pretreatment on canola residues was optimized by using the response surface method (RSM). Based on the fundamental experiments, the real values of factors at the center (0) were determined as follows; $70^{\circ}C$ of temperature, 17.5% of ammonia concentration and 18 h of reaction time in the experiment design using central composition design (CCD). A statistical model predicted that the highest removal yield of lignin was 54% at the following optimized reaction conditions: $72.68^{\circ}C$ of temperature, 18.30% of ammonia concentration and 18.30 h of reaction time. Finally, maximum theoretical yields of soaking in aqueous ammonia pretreatment were 42.23% of glucose and 22.68% of xylose.

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The improvement of the stability of hydrogenated amorphous silicon (수소화된 비정질 실리콘박막의 안정성향상에 관한 연구)

  • 이재희
    • Journal of the Korean Vacuum Society
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    • v.8 no.1
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    • pp.51-54
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    • 1999
  • Hydrogenated amorphous silicon (a-Si:H) films are fabricated by Argon radical annealing (ArRA). The deposition rate of continuously deposited a-Si:H film is 1.9 $\AA$/s. As ArRA time are increased to 0.5 and 1 minute, the deposition rate are increased to 2.8 $\AA$/s and 3.3 $\\AA$/s. The deposition rate of a-si:H films with 2 and 3 minutes ArRA time are 3.3 $\AA$/s. As the ArRA time is increased, the optical band gap and the hydrogen contents in the a-Si:H films are increased and slightly decreased. The light-induced degradation of ArRA treated a-Si:H films are less than that of continuously deposited a-Si:H film. The dark conductivity and the conductivity activation energy ($E_a$) of continuously deposited a-Si:H film are decreased to 1/25 in room temperature and increased to 0.09eV By 1 hour light soaking, respectively. The dark conductivity and $E_a$ of ArRA treated a-Si:H film decreased to 1/3 in room temperature and increased to 0.03eV by 1 hour light soaking, respectively. We could improve the stability of a-Si:H films under the light soaking by ArRA technique and discussed the microscopic process of ArRA technique.

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Effects of Seawater & Freshwater Soaking on the Cure Properties of Accelerated Thermally Aged CSPE (가속열화 된 CSPE의 경화특성에 미치는 해수 담수 침지의 영향)

  • Shin, Yong-Deok;Lee, Jeong-U
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.5
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    • pp.819-824
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    • 2016
  • The accelerated thermal aging of CSPE (chlorosulfonated polyethylene) was carried out for 33.64 and 67.27 days at 110[$^{\circ}C$], equivalent to 40 and 80 years of aging at 50[$^{\circ}C$], respectively. These samples were referred to as CSPE-0y, CSPE-40y and CSPE-80y, respectively. As the accelerated thermally aged years of the CSPE increase, the insulation resistance[$\Omega$] at 20[Hz], 500[Hz], and 2[KHz], and the percent elongation [%EL] of the CSPE decrease. However, the dissipation factor($tan{\delta}$) at 20[Hz], 500[Hz], and 2[KHz], the apparent density[$g/cm^3$], the glass transition temperature and the melting temperature of the CSPE were increased. The period of time that the voltage has to be applied until electric breakdown of the CSPE-0y is longer than that of the CSPE-40y, and the CSPE-80y, but the dielectric strength of the CSPE-80y is lower than that of the CSPE-0y and the CSPE-40y. The differential temperatures after the AC and DC voltages are applied to CSPE-0y, CSPE-40y and CSPE-80y are 0.026~0.028[$^{\circ}C$], 0.030~0.042[$^{\circ}C$], 0.018~0.045[$^{\circ}C$], respectively. The variations of temperature for the AC voltage are higher than those for the DC voltage when an AC voltage is applied to CSPE-0y, CSPE-40y and CSPE-80y. It is found that the dielectric loss owing to the dissipation factor[$tan{\delta}$] is related to the electric dipole conduction current. It is ascertained that the ionic (electron or hole) leakage current is increased by the separation of the branch chain of CSPE polymer from the main chain of the polyethylene as a result of thermal stress due to accelerated thermal aging as well as by conducting ions such as $Na^+$, $Cl^-$, $Mg^{2+}$, $SO_4^{2-}$, $Ca^{2+}$ and $K^+$ after seawater soaking.

Kinetic Study of Hydrations and Volume Change of Soybeans during Soaking (침지중 콩의 흡수 및 부피변화의 속도론적 연구)

  • Kim, Dong-Hee;Yum, Cho-Ae;Kim, Woo-Jung
    • Applied Biological Chemistry
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    • v.33 no.1
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    • pp.18-23
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    • 1990
  • Seven varieties of soybeans(Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2) were investigated to compare the water uptake properties and volume changes during soaking in water. The hydration properties showed that the equilibrated weight increase ratio decreased as the soaking temperature raised to higher than $40^{\circ}C$, while the initial water uptake rate increased upto $80^{\circ}C$. The increase in hydration showed a linear relationship with the square root of the soaking time at $4^{\circ}{\sim}60^{\circ}C$. Local 1 was the highest in water uptake rate constant while Local 2 was the lowest. The activation energy calculated was in the range of $3,246{\sim}4,694\;cal/mole$. The Jangbaek and Local 1 were the highest and the Paldal was the lowest in the rate of volume increase. The activation energy for volume increase was in the range of $3,310{\sim}4,190\;cal/mole$. The z-values calculated from volume change was a little higher than those obtained from weight change.

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The Yield and Growth Responses of Cowpea Sprouts According to the Treatment Conditions of Raw Seeds (원료곡 처리조건에 따른 동부나물 생산량과 생장반응)

  • Kim, Dong-Kwan;Kim, Yong-Soon;Park, Heung-Gyu;Shin, Hae-Ryong;Choi, Kyeong-Ju;Kim, Young-Min;Chon, Sang-Uk
    • Korean Journal of Plant Resources
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    • v.26 no.5
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    • pp.636-644
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    • 2013
  • We examined the effects of soaking, saturation, and aging conditions of raw cowpea seeds, on the yield and growth responses of cowpea sprouts. The absorption caused rapid growth for the first two hours of soaking, then the growth slowed. The longer the soaking period (varied from 1 to 6 hours), the lower the germinability, yield ratio, and lateral root output became. A five-day saturation (moist $96{\pm}1%$, $20^{\circ}C$) treatment led to higher germinability, yield ratio, and lateral root output than no treatment and one- or three-day saturation treatment. High-temperature aging treatment led to lower germinability and yield ratio compared to no such treatment. Taking these findings into account, the optimal treatment conditions of raw cowpea seeds are a five-day saturation (moist $96{\pm}1%$, $20^{\circ}C$) treatment followed by cleaning and growing.

Effect of Soaking and Prechilling Treatment on Seed Germination of Phellodendron amurense Rupr. (침수 및 예냉처리가 황벽나무의 종자 발아에 미치는 영향)

  • Choi, Chung-Ho;Seo, Byeong-Soo
    • Korean Journal of Plant Resources
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    • v.22 no.2
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    • pp.111-115
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    • 2009
  • The seeds of Phellodendron amurense have difficulty to obtain because these plants show dioecism with independent distributions. This experiment was conducted to find the effects of soaking and prechilling treatment on the germination of P. amurense seeds. Seeds were soaked for 3, 5 and 10 days (soaking treatment), and placed on petri-dish at $4^{\circ}C$ for 10, 20, 30 and 50 days after soaked at room temperature for 24 hours (prechilling treatment). After the treatments, germination percentage, mean germination time, germination speed and germination performance index were analyzed. As a result of sowing, prechilled seeds for 30 days had the highest percent of germination, whereas all of the soaked seeds showed lower percent of germination than non-treatment (control). In case of mean germination time, only prechilling for 30 days was more effective than control. In germination speed, all of the soaked seeds had lower values than control whereas all prechilled seeds except prechilled seeds for 20 days showed higher values than control. Especially prechilled seeds for 30 days showed the highest rate among the prechilling treatments. Germination performance index was similar to germination speed.

Effect of retained austenite on mechanical properties in medium carbon steel (중탄소강의 기계적성질에 미치는 잔류오스테나이트의 영향)

  • Sun, C.G.;Kim, Y.H.;Kim, H.G.
    • Journal of the Korean Society for Heat Treatment
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    • v.8 no.3
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    • pp.229-235
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    • 1995
  • We were studied to the effect of alloying element and retained austenite on a mechnical properties and that used steels were composed three types composition. According to the soaking temperature, a retained austenite was pricipitated in the bainitic ferrite matrix and it was pricipitated to a flake type of about $2{\mu}m$, a mixture of massive and bar type and a flake type of about $1{\mu}m$ size. Through x-ray diffraction analysis, the amount of retained austenite was increased with addition of Si and Ni for equal heat treatment condition and it was best abundanted in the soaking temperature of $855^{\circ}C$. The balance value of strength and elongation were complexly controlled not only a retained austenite formation but also a formation characteristic and shape of the retained austenite and bainite. The balance value of strength and elongation were most satisfactory obtained with "B" and "C" specimens in a firstly heat treated at $855^{\circ}C$ and the best result was that a $2840kg/mm^2.%$ with the heat teratment condition of $855^{\circ}C-400^{\circ}C$ used for "C" specimen.

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Relationship between biomass components dissolution (xylan and lignin) and enzymatic saccharification of several ammonium hydroxide soaked biomasses (초본류 3가지 암모니아수 침지 처리에서 바이오매스 성분(자이란과 리그닌) 용출 정도와 효소당화의 관계)

  • Shin, Soo-Jeong;Han, Sim-Hee;Cho, Nam-Seok;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.1
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    • pp.35-40
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    • 2010
  • Corn stover, hemp woody core and tobacco stalk were treated by dilute ammonium hydroxide soaking for improving the enzymatic saccharification of cellulose and xylan to monosaccharides by commercial cellulase mixtures. As more lignin removal by dilute ammonium hydroxide impregnation led to more enzymatic saccaharification of cellulose and xylan to monosaccharides (corn stover vs tobacco stalk). There was no relationship between xylan removal by dilute ammonium hydroxide impregnation and enzymatic saccharification of polysaccharides in pretreated samples. Except corn stover, lower temperature and longer treatment ($50^{\circ}C$-6 day) was less lignin removal than higher temperature and shorter treatment ($90^{\circ}C$ 16 h). Corn stover showed the highest enzymatic saccharification of cellulose and xylan but tobacco stalk showed the lowest.

High Temperature Characteristics of Commercially Available Anion Exchange Membrane for Alkaline Water Electrolysis (알칼리 수전해를 위한 상용 음이온교환막의 고온 특성)

  • JANG, SU-YOEN;RYU, CHEOL-HWI;HWANG, GAB-JIN
    • Journal of Hydrogen and New Energy
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    • v.33 no.4
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    • pp.330-336
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    • 2022
  • In order to evaluate the possibility as a separator in alkaline water electrolysis, the high temperature characteristics were evaluated by measuring the membrane resistance and durability of 5 types of commercial anion exchange membranes in 7 M KOH solution and at 80℃. The membrane resistance of AEM membrane measured in 7 M KOH solution and at 80℃ had a lower value of about 8-24 times compared to the other membranes. The durability of AEM membrane tested with the soaking time in 7 M KOH solution and at 80℃ showed a very good stability and that of FAAM40 and FAAM75-PK showed secondly a good stability. The thermal stability with the soaking time in 7 M KOH solution and at 80℃ of FAAM40 and FAAM75-PK membrane analyzed by thermo-gravimetric analysis showed a good stability compared to the other membranes.

Effects of Seed Disinfectant and Soaking Time on Germination and Disease Occurrence of Adlay, Coix lacryma-jobi L. var. ma-yuen Stapf (율무 종자소독과 침종시간이 발아율 및 병발생에 미치는 영향)

  • Chang, Seog-Won;Jeon, Dae-Hoon;Kim, Hee-Dong;Yi, Eun-Sup;Park, Ki-Jun
    • Korean Journal of Medicinal Crop Science
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    • v.8 no.3
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    • pp.259-265
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    • 2000
  • This study was carried out to investigate the effect of soaking time of seed disinfectant, Fludioxonil on the germination and disease occurrence of adlay (Coix lacryma-jobi L. var. ma-yuen Stapf). The germination rate was higher in the seed disinfectant treatment for 3 days followed by seed soaking for 3 days than that of other treatments under controlled condition of low temperature. The value of two experiments were 90.8%, 96.7%, repectively. And, the time of seed soaking was longer, the more seed rot was proportionly decreased. In the pot and field experiment, germination rates were somewhat low compared to that of petri dish experiment as 88.3%, 84.3%, and occurence of seedling blight showed similar results that of petri dish experiments. There was not significantly different in the yield components among treatments in the field. However, as compared with untreated plot (194kg/10a), unhulled grain yield was increased about 26% on that treatment. Based on these results, it has been thought that improvement of the germonation rate and decrease of disease occurrence of adlay were accompanied with the seed disinfectant during 3 days followed by seed soaking during 3 days before sowing.

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