• Title/Summary/Keyword: rapid hydrolysis

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Preparation of Monodispersed Titania from TPOT (TPOT로부터 단분산 TiO2분말 합성)

  • 안영필;최석홍
    • Journal of the Korean Ceramic Society
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    • v.25 no.6
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    • pp.677-684
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    • 1988
  • Titania powders were obtained from the various hydrolysis condition the variation of Alkoxide, water/Alcohol, REaction, Temp., reaction time and solvent system were investigated. In this result, spherical monodisperesed titania gel powders(≒0.7${\mu}{\textrm}{m}$) were obtained using EtOH(as solvent), and this method had rapid reaction time compare with iso-PrOH(as solvent).

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Characterization of Natural Organic matter by Rapid Mixing Condition (급속교반조건에서 Alum 응집제의 가수분해종 분포특성과 유기물특성변화)

  • Song, Yu-Kyung;Jung, Chul-Woo;Son, Hee-Jong;Sohn, In-Shik
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.4
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    • pp.559-571
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    • 2006
  • The overall objective of this research was to find out the interrelation of coagulant and organic matter during rapid mixing process and to identify the change of organic matter by mixing condition and to evaluate the effect of coagulation pH. During the coagulation, substantial changes in dissolved organics must be occurred by coagulation due to the simultaneous formation of microflocs and NOM precipitates. Increase in the organic removal efficiency should be mainly caused by the removal of microflocs formed during coagulant injection. That is, during the mixing period, substantial amount of dissolved organics were transformed into microflocs due to the simultaneous formation of microflocs and NOM precipitates. The results also showed that 40 to 80% of dissolved organic matter was converted into particulate material after rapid mixing process of coagulation. During the rapid mixing period, for purewater, formation of dissolved Al(III) (monomer and polymer) constant by rapid mixing condition, but for raw water, the species of Al hydrolysis showed different result. During the rapid mixing period, for high coagulant dose, Al-ferron reaction increases rapidly. At A/D(Adsorption and Destabilization) and sweep condition, both $Al(OH)_3(s)$ and dissolved Al(III) (monomer and polymer) exist, concurrent reactions by both mechanism appear to cause simultaneous precipitation.

Assay of Epoxide Hydrolase Activity Based on PCR-linked in vitro Coupled Transcription and Translation System. (무세포 단백질합성 시스템 기반의 epoxide hydrolase 발현 및 활성 분석)

  • Lee, Ok-Kyung;Kim, Hee-Sook;Lee, Eun-Yeol
    • Journal of Life Science
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    • v.15 no.5 s.72
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    • pp.779-782
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    • 2005
  • Cell-free expression is a powerful tool for rapid protein analysis, enabling an efficient identification of gene without cumbersome procedure of transformation and cell culture. Epoxide hydrolase (EH) gene of Rhodotorula glutinis was simply amplified by PCR, and the resultant gene was expressed in vitro using a coupled Transcription/translation system. The cell-free expressed EH protein mixture exhibited the enantioselective hydrolysis activity toward (R)-styrene oxide, representing that cell-free protein synthesis system can be used for the rapid expression of an enantioselective enzyme for an efficient identification of the chiral activity.

The Processing Conditions of Extracts from Rapid Fermented Anchovy Sauce (속성멸치간장엑기스분의 가공조건)

  • Lee, Eung-Ho;Kim, Jin-Soo;Ahn, Chang-Bum;Lee, Kang-Hee;Kim, Myung-Chan;Chung, Bu-Kil;Park, Hee-Yeol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.18 no.2
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    • pp.167-174
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    • 1989
  • AS a part of investigation to use anchovy more effectively as food source, this work was undertaken the processing conditions of extracts from rapid fermented anchovy sauce. To prepare rapid fermented products, the chopped anchovy was mixed with 50% water (w/w), and then hydrolyzed by autolysis or addition of koji under different conditions of hydrolysis. The optimal conditions for hydrolysis of chopped anchovy were revealed $50^{\circ}C$, 6 hours, pH 8.0 by autolysis, and ,$50^{\circ}C$, 6 hours, pH 7.0 by addition of 10% koji, respectively. But, pH control was not much beneficial in increasing yield. The effect of soybean protein isolote for improvement of bitter taste was also tested. The reasonable amount of added soybean protein isolate was revealed 5% on the weight basis of the chopped anchovy. The reaction mixture hydrolyzed under optimal conditions were added with 1% onion powder (w/w), 1% garlic powder(w/w) and 1% red pepper powder(w/w) for masking fishy odor, inactivated for 20 min at $100^{\circ}C$, and then centrifuged for 20 min at 4,000 rpm. The supernatant liquor was filtrated and evaporated to 50%(v/v). finally, table salt was added for bateriostatic effect and characteristic taste of rapid fermented products. the reasonable amount of added table salt was reversed 15% on the volume basis of the evaporated liquor. The hydrolysis ratio of product made by addition of water, product made by addition of koji and water, and product made by addition of soybean protein isolate, koji and water hydrolyzed under optimal conditions were 58.4%, 82.1% and 86.2%, respectively.

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Study of Hydrolysis of Al Powder and Compaction of Nano Alumina by Spark Plasma Sintering(SPS) (Al 분말의 수화 반응과 스파크 플라즈마 열처리법으로 제조된 알루미나 성형체 연구)

  • Uhm Y. R.;Lee M. K.;Rhee C. K.
    • Journal of Powder Materials
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    • v.12 no.6 s.53
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    • pp.422-427
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    • 2005
  • The $Al_2O_3$ with various phases were prepared by simple ex-situ hydrolysis and spark plasma sintering (SPS) process of Al powder. The nano bayerite $(\beta-Al(OH)_3)$ phase was derived by hydrolysis of commercial powder of Al with micrometer size, whereas the bohemite (AlO(OH)) phase was obtained by hydrolysis of nano Al powder synthesized by pulsed wire evaporation (PWE) method. Compaction as well as dehydration of both nano bayerite and bohemite was carried out simultaneously by SPS method, which is used to fabricate dense powder compacts with a rapid heating rate of $100^{\circ}C$ per min. under the pressure of 50MPa. After compaction treatment in the temperature ranges from $100^{\circ}C\;to\; 1100^{\circ}C$, the bayerite and bohemite phases change into various alumina phases depending on the compaction temperatures. The bayerite shows phase transition of $Al(OH)_3{\to}{\eta}-Al_2O_3{\to}{\theta}-Al_2O_3{\to}\alpha-Al_2O_3$ sequences. On the other hand, the bohemite experiences the phase transition from AlO(OH) to ${\gamma}-Al_2O_3\;at\;350^{\circ}C.$ It shows AlO(OH) ${\gamma}-Al_2O_3{\to}{\delta}-Al_2O_3{\to}{\alpha}-Al_2O_3$ sequences. The ${\gamma}-Al_2O_3$ compacted at $550^{\circ}C$ shows a high surface area $(138m^2/g)$.

Development of simultaneous determination of vitamin A and E in infant formula by micro-HPLC (Micro-HPLC를 이용한 조제분유 중 비타민 A.E 동시분석법 개발)

  • Yun I-Ran;Choi You-Jeong;Lee Min-Kwon;Jeong Myeong-Ho;Kim Byeong-Hun
    • Korean Journal of Veterinary Service
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    • v.29 no.3
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    • pp.339-346
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    • 2006
  • Semi-micro-HPLC using a column-switching technique was developed for simultaneous determination of vitamin A and E contents in infant formula. Vitamin A and E were extracted by PDA - HPLC with reversed phase column using organic solvent and their contents in Certified Reference Material (CRM) and infant formula were determined and compared with hydrolysis method and rapid extraction. Developed method has many advantages of simple and rapid sample preparation and simultaneous determination of vitamin A and E by micro-HPLC using reversed phase column.

Physicochemical Properties of Job's Tears (Coix lachryma-jobi L.) Starch Modified with Different Levels of Acid Hydrolysis

  • Kim, Hye-Won;Lee, Kwang-Yeon;Bae, In-Young;Jun, Soo-Jin;Lee, Ji-Yeon;Lee, Hyeon-Gyu
    • Food Science and Biotechnology
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    • v.18 no.5
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    • pp.1145-1149
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    • 2009
  • Physicochemical properties of native and acid-modified Job's tears (Coix lachryma-jobi L.) starches were investigated. Starch extracted from Job's tears was treated with 2.2 N hydrochloric acid for different length of time (3, 6, 12, and 18 hr). The hydrolysis pattern of starches with the acid proceeded rapidly up to 12 hr and then the approached constant values. The swelling power of acid-modified starches measured at all temperatures was lower than that of its native counterparts and the water solubility index increased as temperature and hydrolysis time increased. Rapid visco analyzer viscograms of acid-modified starches demonstrated a very low viscosity as compared with that of native starch. However, Xray diffraction did not show any significant alteration in the crystallinity after acid-modification.

Effects of polymeric Al and hydrolysis products of PAC at different pH on performance of nanofiltration with PAC coagulation pretreatment (PAC 전처리 시 수소이온 농도에 따라 발생 가능한 알루미늄 종에 의한 나노여과막 성능 연구)

  • Choi, Yang-Hun;Kweon, Ji-Hyang
    • Journal of Korean Society of Water and Wastewater
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    • v.24 no.1
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    • pp.15-24
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    • 2010
  • Coagulation can be used for pretreatment of NF membrane filtration. Foulants such as organic matter and particulate can be removed effectively with the process while high flux recovery is maintained. Recently various types of polyaluminium coagulants including polyaluminium chloride(PAC) are commercially available for water treatment. This study examines effects of polymeric Al and hydrolysis products of PAC on nanofiltration membrane performance. Dominant hydrolysis products were polymeric Al, $Al(OH)_3$, and ${Al(OH)_4}^{-1}$ at acidic, neutral, and alkaline pH conditions, respectively. Under acidic pH condition, flux decline was increased with increasing PAC concentrations, possibly due to polymeric Al adsorption on membrane pore and/or surfaces. For neutral and alkaline pH conditions, little flux decline was observed with increasing PAC concentrations except the highest ${Al(OH)_4}^{-1}$ concentration, with which rapid flux decline was shown. Removal of ionic matters was also varied with pH conditions in this study. Especially, conductivity removal was substantially low and $Ca^{2+}$ concentration in the permeate was quite high at neutral pH condition.

Thermal Koji Hydrolysis for Rapid Fermentation of Soy Sauce (간장의 속성제조를 위한 간장국의 고온분해)

  • 류병호;조경자;채영주;박춘옥
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.2
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    • pp.215-221
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    • 1993
  • This study aims to construct the conditions of thermal hydrolysis (40, 45, 5$0^{\circ}C$) of koji for the purpose of rapid soy sauce fermentation. Koji hydrolysate was stable for fermentation, when koji hydrolyzed at 4$0^{\circ}C$ with 12% NaCl or at 45$^{\circ}C$ with 8% NaCl. The highest extracted total nitrogen was 1.75%, when the salt level was 9% and at 45$^{\circ}C$. The amount of reducing sugar was 7.2% and that of formol nitrogen was 0.9% when NaCl concentration was 12% and at 45$^{\circ}C$. The viscosity of koji hydrolyzate was in good condition with 15% NaCl and at 45$^{\circ}C$ until after 12days. On the other hands, free amino acid extracted from koji hydrolyzates showed the highest levels of 3268mg% at 45$^{\circ}C$. Free amino acids consisted of glutamic acid, leucine, arginine, aspartic acid, lysine, valine and phenylalanine which dominated 50% of total amino acids.

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Characteristic of Al(III) Hydrosis Species at Rapid Mixing Condition (급속흔화조건에서 AI(III) 가수분해종의 분포특성)

  • Jung, Chul-Woo;Son, Jung-Gi;Shon, In-Shik;Kang, Lim-Seok
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.2
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    • pp.128-136
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    • 2004
  • The overall objective of this research was to find out the role of rapid mixing conditions in the species of hydrolyzed Al(III) formed by different Al(III) coagulants. When an Al(III) salt is added to water, monomers, polymers, or solid precipitates may form. Different Al(III) coagulants (alum and PACl) show to have different Al species distribution over a rapid mixing condition. During the rapid mixing period, for alum, formation of dissolved Al(III) (monomer and polymer) increases, but for PACl, precipitates of $Al(OH)_{3(s)}$. increases rapidly. Also, for alum, higher mixing speed favoured Al(III) polymers formation over precipitates of $Al(OH)_{3(s)}$ but for PACl, higher mixing speed formed more precipitates of $Al(OH)_{3(s)}$. At A/D and sweep condition, both $Al(OH)_{3(s)}$ and dissolved Al(III) (monomer and polymer) exist, concurrent reactions by both mechanism appear to cause simultaneous precipitation.