• Title/Summary/Keyword: preteatment

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Comparison of pretreatment of fallen leaves for application evaluation by Bio-ethanol raw material (바이오에탄올 원료로서 활용평가를 위한 낙엽의 전처리 비교)

  • Choi, Hyoyeon;Kim, Jaehyung;Pak, Daewon
    • Journal of Energy Engineering
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    • v.23 no.3
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    • pp.241-246
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    • 2014
  • This study is to compare characteristics of saccharification reactions applying to enzymatic hydrolysis of pretreated fallen leaves for bio-ethanol production. It experimented pretreatment of acid, alkaline in the chemical. This experiment includes preteatment of acid and alkaline in chemical, soaking, shaking and autoclaving method, which were applied to biomass. In result, the glucose production from alkaline-NaOH method was 263 mg glucose/ g biomass comparing with them of acid-HCl method. Thus, alkaline-NaOH method is superior than the acid-HCl method for chemical preteatment of fallen leaves. Also, when various chemical treatments were compared, they were all. Based on the results of this study, we found that leaves, one of biomass, are possible in pretreatment and enzymatic hydrolysis process, and they are likely to affect bio-ethanol production in the future.

Study on the Pyro-metallurgical Process for Recovery of Valuable Metal in the Sludge Originated from PCB Manufacturing Process (PCB 제조 공정 중 발생한 슬러지 내 유가금속 회수를 위한 건식야금 공정에 관한 연구)

  • Han, Chulwoong;Son, Seong Ho;Lee, Man-Seung;Kim, Yong Hwan
    • Resources Recycling
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    • v.28 no.6
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    • pp.87-95
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    • 2019
  • This study investigated the effect of process variables for smelting of recovery of valuable metal in the sludge generated from PCB. The moisture and organics in the sludge was removed by preteatment process. The phase equilibria and slag system was selected by thermodynamic phase calculation program and the process variable of pyro-metallurgical process such as reductant. Smelting temperature and holding time for a recovery of valuable metal was studied.

Effects of various Pretreatments on the Nucleation of CVD Tungsten (전처리가 CVD 텅스텐의 핵 생성에 미치는 영향)

  • Kim, Eui-Song;Lee, Chong-Mu;Lee, Jong-Gil
    • Korean Journal of Materials Research
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    • v.2 no.6
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    • pp.443-451
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    • 1992
  • Effects of various pretreatments on the nucleation of CVD-W deposited on the reactively sputter-deposited TiN was investigated. Incubation period of nucleation and deposition rate decreased by the pretreatment of Ar rf-sputter etching for the depth below 300k, but they increased for the etchig depth over 200A. The preteatment of Ar ion implantation decreased the incubation period of nucleation, but increased deposition rate. Also Si$H_4$flushing pretreatment decreased the incubation period of nucleation slightly due to the absorption of Si by TiN surface.

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An Experimental study on the bond strength according to the surface treatment of metal alloy for porcelain fused metal crown (-금속(金屬) 표면처리방법(表面處理方法)에 따른 비귀금속합금(非貴金屬合金)과 도재(陶材)와의 결합강도(結合强度)에 관(關)한 실험적(實驗的) 연구(硏究)-)

  • Chung, In-Sung
    • Journal of Technologic Dentistry
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    • v.11 no.1
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    • pp.83-88
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    • 1989
  • This investigation was performed to evaluate the effect of four different preteatment techniques on the bond strength of porcelain to non-precious metal alloy. Samples of total of 40 were divided into 4 groups according to the 4 variables which included the 50$\mu$alumina oxide air abrasion, method, the as retention bead method, the L-retention bead method, the Etching method. The completed metal-porcelain samples were compressed in Instron loading machine until gross fracture occured to examine the effect of the complex variables on the bond strength of porcelain to non precious metal alloy. The result obtained were as follows : 1. The difference of bond strength according to four different pretreatment techniques was statistically significant(p<0.01). 2. The difference of bond strength between the ss-retention bead method and the L-retention bead method was not significant statistically(p>0.05) 3. The difference of bond strength between the retention bead method and the etching method was statistically significant(p<0.01). 4. The difference of bond strength between the retention bead method and the 50$\mu$alumina oxide air abrasion method was statistically significant(p<0.01). 5. The difference of bond strength between the etching method and the 50$\mu$alumina oxide air abrasion method was statistically significant(p<0.01).

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Optimal Conditions for Improving Enzyme Preteatment Efficiency in Sludge Reduction Process. (슬러지 저감시 효소 전처리의 효율 향상 및 최적화 연구)

  • 김정래;심상준
    • Microbiology and Biotechnology Letters
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    • v.32 no.2
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    • pp.166-171
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    • 2004
  • In this study, we introduced enzymatic pretreatment method, together with ozone treatment for sludge digestion. We optimized the amount of enzyme and ozone, respectively for the successful sludge pretreatment. As a result, we found that as more enzyme is used, higher sludge hydrolysis efficiency was obtained. When we treated sludge by ozone ranging from 0.01g $O_3$/g SS to 0.04 g $O_3$/g SS without enzyme treatment, 0.04 g $O_3$/g SS showed the highest increase of SCOD. Meanwhile, when protease was used together with the same ozone dosage ranges, 0.03g $O_3$/g SS ozonation resulted in the highest increase of SCOD. The sludge pretreatment was optimized by controlling the amount of enzyme and ozone.

Role of Shc and Phosphoinositide 3-Kinase in Heregulin-Induced Mitogenic Signaling via ErbB3

  • Kim, Myong-Soo;Koland, John G.
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.6
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    • pp.507-513
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    • 2000
  • ErbB3/HER3 is a cell surface receptor which belongs to the ErbB/HER subfamily of receptor protein tyrosine kinases. When expressed in NIH/3T3 cells, ErbB3 can form heterodimeric coreceptor with endogenous ErbB2. Among known intracellular effectors of the ErbB2/ErbB3 are mitogen-activated protein kinase (MAPK) and phosphoinositide (PI) 3-kinase. In the present study, we studied relative contributions of above two distinct signaling pathways to the heregulin-induced mitogenic response via activated ErbB3. For this, clonal NIH-3T3 cell lines expressing wild-type ErbB3 and ErbB3 mutants were stimulated with $heregulin{\beta}_1$. While cyclin D1 level was markedly high and further increased by treatment of heregulin in cells expressing wild-type ErbB3, the elimination of either Shc binding or PI 3-kinase binding lowered both levels. This result was supported by the reduction of cyclin $D_1$ expression by preteatment with MAPK kinase inhibitor or PI 3-kinase inhibitor before stimulation with heregulin. In accordance with the cyclin $D_1$ expression, elimination of either Shc binding or PI 3-kinase binding reduced the heregulin-induced DNA synthesis and cell growth rate. Our results obtained by the comparison of wild-type and ErbB3 mutants indicate that the full induction of the cell cycle progression through $G_1/S$ phase by ErbB3 activation is dependent on both Shc/MAPK and PI 3-kinase signal transduction pathways.

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Cryopreservation of Embryogenic Callus in Sweetpotato cv. 'Yulmi' (고구마품종 '율미' 배발생 캘러스의 초저온 동결보존)

  • Park, Jong-Suk;Kim, Suk-Weon;In, Dong-Su;Eun, Jong-Seon
    • Journal of Plant Biotechnology
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    • v.30 no.1
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    • pp.109-113
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    • 2003
  • Cryopreservation of embryogenic callus derived from apical meristem culture was attempted by slow prefreezing method (two-step method) with various cryoprotectants in sweetpotato cv. 'Yulmi' Precultured embryogenic calli on medium containing 10 mg/L ABA prior to slow prefreezing in liquid nitrogen indicated higher survival rate than 1.0 mg/L ABA preteatment. The cryoprotectant comprising 1.28 M DMSO in 0.4 M sucrose solution gave the best survival (over 46%) of sweetpotato cells exposed to liquid nitrogen as determined by TTC reduction and FDA staining method. Cryopreserved calli cultured on MS medium with 1.0 mg/L 2,4-D were grown for 4 weeks in the dark and induced embryos after another 4 weeks. They were subcultured on MS medium supplemented with 0.1 mg/L 2,4-D+0.1 mg/L kinetin for 2 weeks and regenerated into normal plantlets in MS basal medium.

EFFECTS OF AMYLASE ON THE DEMINERALIZATION IN HYDROXYAPATITE (Amylase가 Hydroxyapatite 탈회에 미치는 영향)

  • Lee, In-Hwan;Seo, Jeong-Taeg;Choi, Byung-Jai;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.2
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    • pp.335-351
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    • 1998
  • Salivary proteins which are produced in the saliary acinar cells have been known to be involved in the Calcium and phosphate metabolism. The acquired pellicle resulting from such metabolism is considered as a secondary defence membrane against tooth caries. In this respect, some proteins included in saliva probably play an important role in the prevention of demineralization in enamel. On the other hand, fluoride has long been known to prevent the demineralization of enamel by the inhibition of the growth of Streptococcus mutans(S. mutans) and by the chemical reaction with calcium and phosphate, Therefore, I have examined the roles of amylase and albumin in the demineralization of enamel and compared these preteins with fluoride in terms of anticariogenic effect. 1. The demineralization caused by S. mutans occurred slowly and progressively for the first 60 min, then the rate of demineralization was accelerated afterwards. 2. pH decreased continuously during the entire period of each experiment. 3. The demineralization was significantly inhibited by the preteatment of amylase and fluoride but albumin had little effect on it. 4. An addition of 0.1 mM lactic acid (final concentration 0.1 ${\mu}M$) caused a rapid increase in calcium concentration reaching a maximum within 10 min. 5. pH decreased rapidly by the addition of 0.1 mM lactic acid and reached a minimum within a few seconds followed by an increase in pH. pH reaced a plateu with 10 min. 6. Fluoride, amylase and albumin played little role in the 0.1 mM lactic acid-induced demineralization. 7. A slow infusion of 0.1 M lactic acid at a rate of 5 ${\mu}l/min$ caused a slower increase in calcium concentration compared with the bolus addition of lactic acid. 8. Fluoride had an inhibitory effect on the calcium release caused by slow infusion of lactic acid while amylase and albumin had no effect on it. These results suggest that fluoride inhibits demineralization by protecting the HA from the acid attack whereas amylase has a direct effect on S. mutans to prevent demineralization.

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Radiotherapy Results in Stage IIB Uterine Cervix Cancer (자궁경부암 병기 IIB의 방사선치료결과)

  • Kil Whoon Jong;Chun Mison;Kang Seunghee;Oh Young Taek;Ryu Hee Sug;Ju Hee Jae;Lee Eun Ju
    • Radiation Oncology Journal
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    • v.19 no.4
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    • pp.345-352
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    • 2001
  • Purpose : To evaluate the treatment results and prognostic factors after radiotherapy in stage IIB uterine cervix cancer. Materials and methods : We retrospectively analyzed the records of 90 patients with stage IIB uterine cervix cancer who received radiotherapy between 9/94 and 12/99. Age was ranged from 28 to 79 years (median 57). Tumor size was $\geq4\;cm$ in 64 patients. Preteatment SCC level was measured in 75 patients. Twenty nine patients received conventional radiotherapy (QD) and the others received modified hyper-fractionated radiotherapy (BID). Only 7 patients in BID had tumor size <4 cm. All patients received high dose rate brachytherapy $(4\;Gy\times7\;or\;5\;Gy\times6)$. No Patient received concurrent chemotherapy during radiotherapy. Follow up period was ranging from 9 to 76 months (median 38). Results : The 5-year overall and disease free survival rates were $73.4\%\;and\;71.6\%$, respectively. Local recurrences occurred in $10\%$ of patients, and distant metastasis in $18.9\%$. There was a significant correlation between OS/DFS and tumor size $(<4cm;\;OS\;95.2\%,\;DFS\;91.4\%,\;\geq4cm;\;OS\;63.4\%,\;DFS\;63.4\%)$. Pretreatment SCC level was one of prognostic factors only in univariate analysis. Conclusion : With modified hyperfractionated radiotherapy, there was very low local recurrence rate $(6.6\%)$ and high 5-year overall and disease free survival rate $(75.4\%\;and\;70.5\%)$, which is comparable to results after concurrent chemoradiotherapy in bulky, locally advanced stage IIB uterine cervix cancer.

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Antigenicity of Whey Protein Hydrolysates against Rabbit Anti ${\beta}-Lactoglobulin$ Antiserum (토끼 항 ${\beta}-Lactoglobulin$ 항혈청에 대한 유청단백질 가수분해물의 항원성)

  • Lee, Soo-Won;Ha, Woel-Kyu;Juhn, Suk-Lak;Kim, Jung-Wan;Shon, Dong-Hwa;Lee, Jae-Young
    • Korean Journal of Food Science and Technology
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    • v.26 no.5
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    • pp.532-538
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    • 1994
  • In order to investigate the lowering effects of in vitro enzymatic hydrolysis by the treatment of chymotrypsin, trypsin, pancreatin, or protease from Aspergillus oryzae on the antigenicity of whey protein(WPI) against rabbit anti ${\beta}-LG$ antiserum, competitive inhibition ELISA(cELISA) and passive cutaneous anaphylaxis(PCA) test using guinea pig were performed. The results of cELISA showed that the monovalent antigenicity of the whey protein hydrolysates(WPH) to the antiserum was decreased to $10^{-1.7}{\sim}10^{-4.1}$ and less by the hydrolysis. Especially, the antigenicity of OUP(hydrolysate by protease from Asp. oryzae with preteatment of pepsin) was found almost to be removed. By the heterologous PCA the polyvalent antigenicity of the WPH was decreased to $1/2{\sim}1/128$ and less. Especially, the polyvalent antigenicity of OUN(hydrolysate by protease from Asp. oryzae without preteatments) was found almost to be removed, although OUN did not have so high degree of hydrolysis(DH) or so low monovalent antigenicity (reduced to $10^{-3.2}$). Therefore, this result was assumed to come from effective destruction of antigenic determinants on ${\beta}-LG$ in WPI, not to produce polyvalent antigenic peptides that are closely associated with induction of allergy. This finding suggested that WPH prepared by the treatment of microorganic protease from Asp. oryzae would be a material for hypoallergenic infant formula due to the removal of the polyvalent antigenicity of ${\beta}-LG$, the major milk allergen in WPI.

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