• 제목/요약/키워드: Buffer capacity

검색결과 361건 처리시간 0.024초

Electrokinetic정화시 토질의 완충능을 고려한 시료내의 pH변화 (pH Variation In Soils Considering Buffer Capacity during Electrokinetic Extraction)

  • 오승록;한상재;김수삼;조성호
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.585-590
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    • 2001
  • Physicochemical phenomena in soils are dependent upon pH when using electrokinetic extraction for the contaminants removal especially for heavy metals. pH variation in soils is affected on H$\^$+/ and OH ̄ ions produced by electrolysis reaction and buffer capacity of soil. High amount of heavy metals are retained in the soils if the soil buffer capacity remains high enough to resist a change in pH. Therefore, accurate pH estimation of soil is important in the application of electrokinetic mechanism for decontamination and understanding of subsurface physicochemical characteristics is also required as well as considering buffer capacity for the enhanced methods application. For these, buffer capacity and pH distribution were measured for the four soils, and also compared with modeling results. The results of buffer modeling were good agreement with experimental data. It is showed that four soils were effected by buffer capacity

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Three Buffer 맥동관 냉동기에 관한 실험적 연구 (An Experimental Study of a Therr Buffer Pulse Tube Refrigerator)

  • 박성재;고득용;김효봉;신완순
    • 한국초전도ㆍ저온공학회논문지
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    • 제1권2호
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    • pp.54-59
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    • 1999
  • An experimental study was carried out to improve the cooling capacity and performance of the pulse tube refrigerator. Three buffer pulse tube refrigerator was designed and fabricated, and the experimental apparatus operating process of the therr buffer pulse tube refrigerator and results obtained with the performance test. The cooldown characteristics and load characteristics are described. The lowest temperature measured in the three buffer pulse tube refrigerator was 88K and the cooling capacity at the optimum operating condition was 27 W at 120K.

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하계 한국 남부해역 표층수의 탄산계 완충역량 (The Buffer Capacity of the Carbonate System in the Southern Korean Surface Waters in Summer)

  • 황영빈;이동섭
    • 한국해양학회지:바다
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    • 제27권1호
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    • pp.17-32
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    • 2022
  • 2020년 8월 한국 남부해역 해양 조사를 통해 수집된 수온, 염분, 용존무기탄소(DIC), 총알칼리도(TA) 자료를 사용해서 표층수의 완충역량을 정량화하였다. 기존의 Revelle 인자의 문제점을 보완한 여섯 가지 완충 인자의 지리적 분포와 변동성을 분석하고, 수문학적 요인인 수온, 염분과의 관계를 논의하였다. 모든 완충인자들은 수괴에 따른 공간적 분포를 보였다: 완충역량은 용승이 발생했던 동해표층혼합수(ESMW)와 남해표층혼합수(SSMW)에서 낮았으며, 황해표층수(YSSW)에서는 중간값을 보였다. 또한 고온인 대마난류수(TWC)와 장강희석수(CDW) 순으로 크게 나타났다. 이는 하계의 장강유출수가 연구해역의 완충역량을 강화하는 것을 의미하며, 높은 수온과 생물학적 생산력, 하계의 성층화에 의한 혼합 약화가 원인으로 판단된다. 수온-완충역량은 수괴와 상관없이 유의한 양의 상관관계(R2=0.79)를 보였으나 염분-완충역량은 약한 음의 상관관계(R2=0.30)를 보였다. 높은 수온은 열역학적 과정인 기체 교환과 탄산계 화학종 분배를 통해 완충역량을 강화한다. 염분의 경우는 연구해역의 표층 염분이 증발이나 강수가 아닌 국지적인 담수의 유입과 용승수와의 혼합에 의해 변하므로 염분과 완충역량의 관계가 역전된다.

Alum 제지슬러지의 pH 완충능과 산성화저항성 (pH Buffer Capacity and Acidification Resistance of Alum Paper Mill Sludge)

  • 이인복;장기운
    • 한국토양비료학회지
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    • 제32권1호
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    • pp.1-6
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    • 1999
  • To find the latent effect of paper mill sludges (PMS) with and without alum, and alum paper mill sludge compost(PMSC) on aluminum toxicity of crops, the pH buffer capacity and the acidification resistance index (ARI) for PMSs and PMSC were investigated, comparing to upland soil. Buffer capacities of PMS with and without alum, and PMSC were significantly higher than $2.5cmol^+kg^{-1}$ of check soil as 137, 250, and $147cmol^+kg^{-1}$, respectively. Owing to such high buffer capacity of PMS and PMSC, they showed to be well-resisted to acidification.

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On-line Monitoring of IPTG Induction for Recombinant Protein Production Using an Automatic pH Control Signal

  • Hur Won;Chung Yoon-Keun
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권4호
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    • pp.304-308
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    • 2005
  • The response of IPTG induction was investigated through the monitoring of the alkali consumption rate and buffer capacity during the cultivation of recombinant E. coli BL21 (DE3) harboring the plasmid pRSET-LacZ under the control of lac promoter. The rate of alkali consumption increased along with cell growth, but declined suddenly after approximately 0.2 h of IPTG induction. The buffer capacity also declined after 0.9 h of IPTG induction. The profile of buffer capacity seems to correlate with the level of acetate production. The IPTG response was monitored only when introduced into the mid-exponential phase of bacterial cell growth. The minimum concentration of IPTG for induction, which was found out to be 0.1 mM, can also be monitored on-line and in-situ. Therefore, the on-line monitoring of alkali consumption rate and buffer capacity can be an indicator of the metabolic shift initiated by IPTG supplement, as well as for the physiological state of cell growth.

토양의 산/염기 완충능의 모델링 (Modeling of Acid/Base Buffer Capacity of soils)

  • 김건하
    • 한국토양환경학회지
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    • 제3권3호
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    • pp.3-10
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    • 1998
  • 토양의 산/염기 완충능은 토양-오염물질-공극수로 이루어진 시스템의 pH에 직접적인 영향을 미치므로 오염물질의 토양내 거동예측시에 많은 영향을 미치는 매우 중요한 토양의 성질이다. 본 연구는 이중확산층이론과 two layer electrostatic 흡착모델을 응용하여 토양의 산/염기 완충능의 이론모델을 유도하고 이 모델의 적용절차를 제시하였다. 산-염기 적정실험을 통하여 두 종류의 카올리나이트의 완충능을 실측하고 이를 본 연구에서 개발된 모델의 예측치와 비교하였다.

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유연생산(柔軟生産)시스템에서의 버퍼시스템 설계(設計) (Buffer System Design in the Flexible Manufacturing System Environments)

  • 강희정;김환성;조남호
    • 품질경영학회지
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    • 제20권2호
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    • pp.118-128
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    • 1992
  • The determination of appropriate buffer capacity is an important issue in the design of the advanced manufacturing systems and closely related to the system efficiency and flexibility. Work-in-process is usually not desirable. However, in reality, maintaining some capacity of buffer storage is inevitable in compensation for the machine blocking and break down. The objective of this paper is to present analytical methods and tools for the buffer capacity planning in the Flexible Manufacturing System Environments. The effects when machine blocking is critical factor are also discussed.

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Deadlock과 Workload에 따른 FMS의 버퍼 Capacity 결정에 관한 연구 (A Study of Buffer Allocation in FMS based on Deadlock and Workload)

  • 김경섭;이정표
    • 한국시뮬레이션학회논문지
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    • 제9권2호
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    • pp.63-73
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    • 2000
  • Due to the complexity of part flow and limited resources, FMS(Flexible Manufacturing System) develops blocking, starvation and deadlock problems, which reduce its performance. In order to minimize such problems buffers are imposed between workstations of the manufacturing lines. In this paper, we are concerned with finding the optimal buffer allocation with regard to maximizing system throughput in limited total buffer capacity situation of FMS. A dynamic programming algorithm to solve the buffer allocation problem is proposed. Computer simulation using Arena is experimented to show the validation of the proposed algorithm.

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스펙트럼 핸드오프 호를 위해 버퍼를 활용하는 무선인지시스템의 얼랑 용량 (Erlang Capacity of Cognitive Radio Systems Utilizing Buffer for Spectrum Handoff Calls)

  • 팜티홍츄;구인수
    • 한국인터넷방송통신학회논문지
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    • 제10권1호
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    • pp.145-150
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    • 2010
  • 본 논문은 무선인지시스템이 갖는 얼랑 용량을 분석하였다. 무선 인지 사용자들의 신규 호 및 스펙트럼 핸드오프를 요청하는 호들에 대해 버퍼를 사용하는 무선 자원 관리 기법을 고려하였으며, 성능 분석을 위해 마르코프(Markov) 모델을 사용하였다. 이를 기반으로 무선 인지 시스템에서 기사용자 및 무선 인지 사용자가 겪는 호 차단(call blocking) 확률, 강제 호 종료(forced call termination) 확률, 호 서비스 비완료(non-completion) 확률 등을 유도하였다. 시뮬레이션을 통해 버퍼의 크기가 증가함에 따라, 인지 무선 시스템에서 수용될 수 있는 얼랑 용량 또한 증가함을 보였다.

AnnAGNPS 모형을 이용한 수변구역의 비점오염물질 제거능 산정 (Estimation of Nonpoint Pollutant Removal Capacity in the Buffer Strip with AnnAGNPS Model)

  • 박윤희;김태근
    • 한국환경복원기술학회지
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    • 제9권5호
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    • pp.22-31
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    • 2006
  • AnnAGNPS model would be applied to simulate the pollutant removal capacity with the buffer strip in the Deachung reservoir watershed. In 2002, 2,270 tons of TN and 221 tons of TP were discharged from the nonpoint source pollutants in this watershed. During the rainy season, from June to September, 66.4% of TN and 71.9% of TP resulted from nonpoint source loads. AnnAGNPS model was also used to simulate the nutrients removal capacity from the buffer strip under the condition that the present landuse would be changed to forest. As the result of simulation, the removal rates of nutrients from the buffer strip of Daecheong reservoir watershed are 406 tons of TN, 39 tons of TP, which means reduction rates are TN 17.9%, TP 17.8%, respectively.