• Title/Summary/Keyword: Buffer capacity

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

  • 오승록;한상재;김수삼;조성호
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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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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An Experimental Study of a Therr Buffer Pulse Tube Refrigerator (Three Buffer 맥동관 냉동기에 관한 실험적 연구)

  • 박성재;고득용;김효봉;신완순
    • Progress in Superconductivity and Cryogenics
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    • v.1 no.2
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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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The Buffer Capacity of the Carbonate System in the Southern Korean Surface Waters in Summer (하계 한국 남부해역 표층수의 탄산계 완충역량)

  • HWANG, YOUNGBEEN;LEE, TONGSUP
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.27 no.1
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    • pp.17-32
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    • 2022
  • The buffer capacity of southern Korean waters in summer was quantified using data set of temperature, salinity, dissolved inorganic carbon, total alkalinity obtained from August 2020 cruise. The geographical distribution and variability of six buffer factors, which amended the existing Revelle factor, are discussed their relationship with the hydrological parameters of temperature and salinity. The calculated results of six buffer factors showed the spatial variations according to the distributions of various water masses. The buffer capacity was low in the East Sea Surface Mixed Water (ESMW) and South Sea Surface Mixed Water (SSMW) where upwelling occurred, and showed an intermediate value in the Yellow Sea Surface Water (YSSW). In addition, the buffer capacity increased in the order of high temperature Tsushima Warm Current (TWC) and Changjiang Diluted Water (CDW). This means that the Changjiang discharge water in summer strengthens the buffer capacity of the study area. The highest buffer capacity of CDW is due to its relatively higher temperature and biological productivity, and a summer stratification. Temperature showed a good positive correlation (R2=0.79) with buffer capacity in all water masses, whereas salinity exhibited a poor negative correlation (R2=0.30). High temperature strengthens buffer capacity through thermodynamic processes such as gas exchange and distribution of carbonate system species. In the case of salinity, the relationship with buffer capacity is reversed because salinity of the study area is not controlled by precipitation or evaporation but by a local freshwater input and mixing with upwelled water.

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

  • Lee, In-Bog;Chang, Ki-Woon
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.1
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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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    • v.10 no.4
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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.

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

  • 김건하
    • Journal of Korea Soil Environment Society
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    • v.3 no.3
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    • pp.3-10
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    • 1998
  • Acid/Base buffer capacity of soil is very important in prediction of contaminant transport for its direct impact on pH change of the system composed of soil-contaminant-water, In this research, diffuse double layer theory as well as two layer electrostatic adsorption model are applied to develop a theoretical model of buffer capacity of soil. Model application procedures are presented as well. Buffer capacity of Georgia kaolinite and Milwhite kaolinite was measured by acid-base titration. Model prediction and experimental results are compared.

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

  • Gang, Hui-Jeong;Kim, Hwan-Seong;Jo, Nam-Ho
    • Journal of Korean Society for Quality Management
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    • v.20 no.2
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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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A Study of Buffer Allocation in FMS based on Deadlock and Workload (Deadlock과 Workload에 따른 FMS의 버퍼 Capacity 결정에 관한 연구)

  • 김경섭;이정표
    • Journal of the Korea Society for Simulation
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    • v.9 no.2
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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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Erlang Capacity of Cognitive Radio Systems Utilizing Buffer for Spectrum Handoff Calls (스펙트럼 핸드오프 호를 위해 버퍼를 활용하는 무선인지시스템의 얼랑 용량)

  • Pham, Thi Hong Chau;Koo, In-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.1
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    • pp.145-150
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    • 2010
  • In this paper, the performance of cognitive radio network is analyzed in terms of Erlang capacity. To improve the Erlang capacity with respect to primary user (PU) and secondary user (SU) traffic, we propose an efficient radio resource management scheme utilizing the buffer for new SUs and interrupted SUs. Markov model is developed, and analyzed to derive the performances of the proposed spectrum sharing scheme in both primary system and secondary system. To determine the Erlang capacity region, the blocking probability, the forced termination probability and the non-completion probability are calculated. Simulation results provide insight into the advantages of the buffer utilization. It is observed that the supportable traffic loads of PU and SU can be increased significantly according to the buffer length.

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

  • Park, Yun Hee;Kim, Tae Geun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.5
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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.