• 제목/요약/키워드: Exchange times

검색결과 816건 처리시간 0.024초

Immobilization of transgenic Nicotiana tabacum cell suspensions for the continuous production of hGM-CSF

  • Roh, Yun-Sook;Lee, Sang-Yoon;Kim, Dong-Il
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2003년도 생물공학의 동향(XIII)
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    • pp.341-345
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    • 2003
  • 형질전환된 담배세포 배양을 이용한 hGM-CSF 생산에 있어 polyurethane foam 내 고정화법을 이용하여 연속배양의 가능성을 확인하였고 spinner flask에서의 배양에 따른 영향을 알아보았다. 16일 동안 3번의 배지교환에도 세포의 활성이 유지되어 hGM-CSF 생산량은 계속적으로 증가하였다. 온도와 교반속도를 동일하게 하였을 때 spinner flask에서의 hGM-CSF 생산량은 17.3 ${\mu}g/L$으로 100-mL flask의 9.8 ${\mu}g/L$보다 증가하였다. 따라서 최적의 배지교환 속도와 양을 결정하여 spinner flask에서 연속배양을 실시할 경우 세포 재사용이라는 경쟁력과 함께 높은 hGM-CSF 생산량이 얻어질 것으로 예상된다.

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Pretreatment Process for Performance Improvement of SIES at Kori Unit 2 in Korea

  • Lee, Sang-Jin;Yang, Ho-Yeon;Shin, Sang-Woon;Song, Myung-Jae
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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    • pp.12-27
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    • 2004
  • Pretreatment process consisted of submerged hollow-fiber microfiltration(HMF) membrane and spiral-wound nanofiltration(SNF) membrane has been developed by NETEC, KHNP for the purpose of improving the impurities of liquid radioactive waste before entering Selective Ion Exchange System(SIES). The lab-scale combined system was installed at Kori NPP #2 nuclear power plant and demonstration tests using actual liquid radioactive waste were carried out to verify the performance of the combined system. The submerged HMF membrane was adopted for removal of suspended solid in liquid radioactive waste and the SNF membrane was used for removal of particulate radioisotope such as, Ag-l10m and oily waste because ion exchange resin can not remove particulate radioisotopes. The liquid waste in Waste Holdup Tank (WHT) was processed with HMF and SNF membrane, and SIES. The initial SS concentration and total activity of actual waste were 38,000ppb and $1.534{\times}10_{-3}{\mu}Ci/cc$, respectively. The SS concentration and total activity of permeate were 30ppb and lower than LLD(Lower Limit of Detection), respectively.

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한국학교보건학회의 발전과정과 전망에 관한 논고 (An Analytical Study of the Development, Improvement, and Direction of the Korean Society of School Health)

  • 김영임
    • 한국학교보건학회지
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    • 제11권1호
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    • pp.123-130
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    • 1998
  • The Korean society of School Health was opened to research school health, publish a Journal, survey activities, educate members, and exchange information etc This society has operated these services actively since 1987. The objectives of this study are (1) To review the quantitative development process of the society of school health (2) To review the qualitative development process of the society. (3) To suggest improvement and new directions of the society The quantitative aspects include number of members, number of conferences, and number of journals published; the qualitative aspects deal with comprehension and sufficiency of these activities A literature review method was used for this study The results are as follows. (1) The number of members increased to 987 from 200 (2) The number of conferences total led 15 at an average of 1 5 per year since 1987 (3) The journal of the Korean society of school health was published a total of 20 times at an average of 2 per year. (4) Many health behavior and student-oriented articles were published (5) There are few activities that exchange international information, suply data to members, and investigate the opinions of society concerning school health Consequently, positive activities concerning major school health themes, research concerning the health rights of teachers in a school environment, and a more systematic management of members should be developed. Also, it is necessary to develope an in-service education program for those same members.

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양이온 물질로 오염된 지하수 정화를 위한 반응벽체 개발 : 제올라이트의 적용성 평가

  • 이승학;이재원;김시현;박준범;박상권
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.23-26
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    • 2001
  • Batch test and column test were performed to develop the design factors for PRBs against the contaminated groundwater by ammonium and lead. Clinoptilolite, one of the natural zeolites having excellent cation exchange capacity(CEC), was chosen as the reactive material through the ion-exchange mechanism. In the batch test, the reactivity of Clinoptilolite to ammonium and lead was examined with varying the particle size of Clinoptilolite. The nit weight of Clinoptilolite showed removal efficiencies of 65 % against the ammonium and 98% against lead. The effect of particle size of Clinoptilolite was not noticeable. In the column test, the permeability was examined using flexible-wall permeameters with varying the particle size of Clinoptilolite. When the washed Clinoptilolite having the diameter of 0.42-0.85 nm was mixed with Jumunjin sands in 20:80 ratio (w/w), the highest permeability of 2$\times$10$^{-3}$ -7 x 10$^{-4}$ cm/s was achieved. The reactivity and the strength property of the mixed material were investigated using fixed wall column having 8 sampling ports on the wall and the direct shear test, respectively. Clinoptilolite was found to be a suitable material for PRBs against the contaminated groundwater with ammonium and/or heavy metals.

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동일 전열면적을 갖는 용접식 판형열교환기와 관류형 열교환기의 성능 비교 (Performance Comparison of a Welded Plate Heat Exchanger and Shell and Tube Heat Exchanger with Same Heat Transfer Area)

  • 함정균;김민준;안성국;조홍현
    • 한국지열·수열에너지학회논문집
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    • 제15권4호
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    • pp.46-54
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    • 2019
  • In this study, the performance of a shell and tube heat exchanger (STHE) and welded plate heat exchanger (WPHE) was measured experimentally. The pass numbers of the STHE was changed by 1, 2 and 4. As a result, the WPHE showed 2.1 times higher heat exchange capacity than that of the STHE. In case of pressure drop, the STHE with 1 and 2 pass number has a lower pressure drop than the WPHE, while the STHE with 4 pass presented higher pressure drop than the WPHE. The performance index considering the heat exchange capacity and pump consumption power, showed in oder of STHEPass1 > STHEPass2 > W PHE > STHEPass4 under the same flow rate. Therefore, when the WPHE was designed optimally under same operating condition with STHE, the maintenance fee and space can be reduced effectively by using the WPHE.

Decomposition of PVC and Ion exchange resin in supercritical water

  • Lee, Sang-Hwan;Yasuyo, Hosgujawa;Kim, Jung-Sung;Park, Yoon-Yul;Hiroshi, Tomiyasu
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2005년도 봄 학술발표회지 제14권(제1호)
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    • pp.267-271
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    • 2005
  • This experiment was carried out at 450"C, which is relatively lower than the temperature for supercritical water oxidation (600-650$^{\circ}C$). In this experiment, the decomposition rates of various incombustible organic substances were very high. In addition, it was confirmed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium(salt formation).However, to raise the decomposition rate, relatively large amount of sodium nitrate(3-4 times the equivalent weight) was required. When complete oxidation is intended as in the case with PCB, the amount of oxidizer and decomposition cost is important. But when vaporization reduction is required as in the case with nuclear wastes, the amount of radioactive wastes increases instead. But as can be seen in the result of XRD measurement, unreacted sodium nitrate remained unchanged. If oxidation reaction of organic substance simply depends on collision frequency, unreacted sodium nitrate can be recovered and reused, then oxidation equivalent weight would be sufficient. In the gas generated, toxic gas was not found. As the supercritical water medium has high reactivity, it is difficult to generate relatively low energy level SO$_{X}$, and NO$_{X}$.

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Evaluation of 0ff-gas Characteristics in Vitrification Process of ion-Exchange Resin

  • Park, S. C.;Kim, H. S.;K. H. Yang;C. H. Yun;T. W. Hwang;S. W. Shin
    • Nuclear Engineering and Technology
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    • 제33권1호
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    • pp.83-92
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    • 2001
  • The properties of off-gas generated from vitrification process of ion-exchange resin were characterized. Theoretical composition and flow rate of the off-gas were calculated based on chemical composition of resin and it's burning condition inside CCM. The calculated off-gas flow rate was 67.9Nm$^3$/h at the burning rate of 40kg/h. And the composition of off-gas was avaluated as $CO_2$(41.4%), steam(40.0%), $O_2$(13.3%), NO(3.6%), and SO$_2$(1.6%) in order. Then, actual flow rate and composition of off-gas were measured during pilot-scale demonstration tests and the results were compared with theoretical values. The actual flow rate of off-gas was about 1.6 times higher than theoretical one. The difference between theoretical and actual flow rates was caused by the in-leakage of air to the system, and the in-leakage rate was evaluated as 36.3Nm$^3$/h. Because of continuous change in the combustion parameters inside CCM, during demonstration tests, the concentration of toxic gases showed wide fluctuation. However, the concentration of CO, a barometer of incompleteness of combustion inside CCM, was stabilized soon. The result showed quasi-equilibrium state was achieved two hours after feeding of resin.

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컴퓨터 통합형 전화서비스를 위한 Java 기반의 호제어 시스템 설계 (Design of the Java-based Call Control System for CTI(Computer Telephony Integration) Service)

  • 유창열;복혁규;최재원
    • 한국컴퓨터정보학회논문지
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    • 제8권1호
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    • pp.97-102
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    • 2003
  • 본 논문에서는 기반 통신 인프라를 사용하여, 안정적인 시스템 운영과 상호 운용성 확보, 동시 접속자를 고려하는 컴퓨터 통합형 전화 서비스를 위한 Java기반의 호제어 시스템을 설계하였다. 호제어 시스템의 성능평가는. 사용자가 10명일 때보다는 20명 이상일 때 일정한 응답시간과 시스템의 안정화를 가져왔으며, 100명 이상의 사용자 동시접속 요청에 있어서도 1초 이내에 신속한 응답시간이 이루어져, 모든 플랫폼에서 안정적인 시스템 운영과 상호 운용성 확보는 물론 빠른 접속율과 우수한 성능을 나타내었다.

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미성숙 쥐 자궁에서 Tamoxifen의 Antiestrogen 효과에 관한 연구 : I. 세포질 내 및 핵 내 Estradiol 수용체 농도의 변화에 관하여 (A Study on Antiestrogenic Effects of Tamoxifen in Immature Rat Uterus; I. Effects on Concentrations of Cytosol and Nuclear Estradiol Receptor)

  • 이효종;조충호;박무현
    • 대한수의학회지
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    • 제25권2호
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    • pp.187-195
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    • 1985
  • The Present study has been carried out to elucidate the antiestrogenic effects of tamoxifen in uteri of immature rats. Immature female Sprague-Dawley rats were allocated into 4, groups and injected with $5{\mu}g$ of estradiol-$17{\beta}$, $50{\mu}g$ of tamoxifen, a combination of both or vehicle only subcutaneously three times after an interval of 24 hours respectively. The concentrations, of cytosol estradiol receptor in uterus were measured by DCC method before and 1, 3, 6, 12, 24, 48 and 72 hours after the above treatments and those of nuclear estradiol were measured by protamine exchange method 72 hours and those of nuclear estradiol were measured by protamine exchange method 72 hours after the above treatments. The results obtained were summarized as follows: 1. The binding affinity of tamoxifen to estradiol receptor in uterine cytosol was lower than that of estradiol-$17{\beta}$, accordingly the translocation of estradiol receptor into the nucleus was found to be delayed. 2. Tamoxifen caused the retention of estradiol receptor in nucleus over 24 hours and inhibited the replenishment of the receptor from nucleus to cytosol in uterus.

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유황의 친핵 치환반응 (제3보). 아세톤 용매속에서의 Dimethylsulfamoyl Chloride의 할라이드 교환반응에 관한 속도론적 연구 (Nucleophilic Displacement at Sulfur Center (III). Kinetic Studies on Halide Exchange Reactions of Dimethylsulfamoyl Chloride in Dry Acetone)

  • 이익춘;김시준
    • 대한화학회지
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    • 제17권6호
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    • pp.406-410
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    • 1973
  • Dimethylsulfamoyl chloride의 할라이드 교환반응을 무수 아세톤 용매속에서 방사성 할라이드 이온을 사용하여 두 온도에서 속도론적으로 연구하였다. 그 결과를 benzensulfonyl chloride의 경우와 비교해 보면 친핵성에 있어서는 거의 비슷한 경향성을 나타내나, 반응속도는 dimethylsulfamoyl chloride 쪽이 $10^{-2}$배 이상이나 느린 경향을 나타낸다. 또한 활성화 파라미터, ${\Delta}H^{\neq}$${\Delta}S^{\neq}$는 benzensulfonyl chloride의 경우와는 반대로 dimethylsulfamoyl chloride의 경우는 $Cl^-\;>\;Br^-\;>\;I^-$의 순서로 감소함을 나타낸다. 이 결과를 bond-breaking, bond formation, electronic requirment 및 HSAB 원리로 설명하였다.

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