• Title/Summary/Keyword: stripping

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Effect of Pre-NH3 Stripping on the Advanced Sewerage Treatment by BNR (BNR에 의한 하수의 고도처리에 미치는 NH3 스트리핑 전처리의 영향)

  • Seo, Jeong-Beom;An, Kwang-Ho
    • Journal of Korean Society on Water Environment
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    • v.22 no.5
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    • pp.846-850
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    • 2006
  • The biological nutrient removal from domestic wastewater with low C/N ratio is difficult. Therefore, this study was performed to increase influent C/N ratio by ammonia stripping without required carbon source and for improving treatment efficiencies of sewerage by the combination process of ammonia stripping and BNR (StripBNR). The results of this study were summarized as follows. BOD removal efficiencies of BNR and StripBNR were 95.3% and 93.2%, respectively. T-N and T-P removal efficiencies of BNR were 53.3% and 40.8%, respectively. T-N and T-P removal efficiencies of StripBNR were 72.8% and 62.9%, respectively. Concentrations of $NH_3-N$, $NO_2-N$ and $NO_3-N$ at BNR effluent were 0.03 mg/L, 0.08 mg/L and 9.12 mg/L, respectively. On the other hands, concentrations of $NH_3-N$, $NO_2-N$ and $NO_3-N$ at StripBNR effluent were 5.79 mg/L, 0.01 mg/L and 0.14 mg/L, respectively. Consequently, influent C/N ratio of BNR process was increased by ammonia stripping. Removal efficiency of T-N and T-P was improved about 20% by the process of StripBNR.

Determination of Ag(Ⅰ) Ion at a Modified Carbon Paste Electrode Containing N,N'-Diphenyl Oxamide

  • Won, Mi-Sook;Yeom, Jeong-Sik;Yoon, Jang-Hee;Jeong, Euh-Duck;Shim, Yoon-Bo
    • Bulletin of the Korean Chemical Society
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    • v.24 no.7
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    • pp.948-952
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    • 2003
  • New approach for the determination of Ag(I) ion was performed by using a carbon paste electrode (CPE) containing N,N'-Diphenyl oxamide (DPO) with anodic stripping voltammetry. The CMEs have been prepared by making carbon paste mixtures containing an appropriate amount of DPO salt coated onto graphite particles to analyze trace metal ions via complexation followed by stripping voltammetry. Various experimental parameters affecting the response, such as pH, deposition time, temperature, and electrode composition, were carefully optimized. Using differential pulse anodic stripping voltammetry, the logarithmic linear response range for the Ag(I) ion was 1.0 × $10^{-7}$ - 5.0 × $10^{-9}$ M at the deposition time of 10 min, with the detection limit was 7.0 × $10^{-10}$ M. The detection limit adopted from anodic stripping differential pulse voltammetry was 7.0 × $10^{-10}$ M for silver and the relative standard deviation was ± 3.2% at a 5.0 × $10^{-8}$ M of Ag(I) ion (n = 7). The proposed electrode shows a very good selectivity for Ag(I) in a standard solution containing several metals at optimized conditions.

Determination of Ultra Trace Levels of Copper in Whole Blood by Adsorptive Stripping Voltammetry

  • Attar, Tarik;Harek, Yahia;Larabi, Lahcen
    • Journal of the Korean Chemical Society
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    • v.57 no.5
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    • pp.568-573
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    • 2013
  • A selective and sensitive method for simultaneous determination of copper in blood by adsorptive differential pulse cathodic stripping voltammetry is presented. The procedure involves an adsorptive accumulation of Cu(II)-ETSC (4- ethyl-3-thiosemicarbazide) on a hanging mercury drop electrode, followed by a stripping voltammetry measurement of reduction current of adsorbed complex at about -715 mV. The optimum conditions for the analysis of copper (II) ion are : pH 10.3, concentration of 4-ethyl-3-thiosemicarbazide $3.25{\times}10^{-6}$ M and an accumulation potential of -100 mV. The peak current is proportional to the concentration of copper over the range 0.003-125 ng/mL with a detection limit of 0.001 ng/mL and an accumulation time of 60 s. Moreover, with the use of the proposed method, there is a considerable improvement in the detection limit, the linear dynamic range and the deposition time, compared with the methods of adsorptive stripping voltammetry for the determination of copper. The developed method was validated by analysis of whole blood certified reference materials.

Resolving the Ambiguities of Negative Stripping Construction in English : A Direct Interpretation Approach (영어 부정 스트리핑 구문의 중의성 해소에 관한 연구: 직접 해석 접근법을 중심으로)

  • Kim, So-jee;Cho, Sae-youn
    • Cross-Cultural Studies
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    • v.52
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    • pp.393-416
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    • 2018
  • Negative Stripping Construction in English involves the disjunction but, the adverb not, and a constituent NP. This construction is an incomplete sentence although it delivers a complete sentential meaning. Interpretation of this construction may be ambiguous in that the constituent NP can either be construed as the subject, or as the complements including the object. To generate such sentences and resolve the issue of ambiguity, we propose a construction-based analysis under direct interpretation approach, rejecting previous analyses based on deletion approaches. In so doing, we suggest a negative stripping construction rule that can account for ambiguous meaning. This rule further can enable us to explain syntactic structures and readings of Negative Stripping Construction.

ISM truncation due to ram pressure stripping: Comparisons of Theoretical Predictions and Observations

  • Lee, Seona;Sheen, Yun-Kyeong;Yoon, Hyein;Chung, Aeree;Jaffe, Yara
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.77.1-77.1
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    • 2019
  • It has been proposed by Gunn & Gott (1972) that galaxies may lose their interstellar gas by ram pressure due to the dense intra-cluster medium while falling to the cluster potential. The observational evidence for this process, which is known as ram pressure stripping, is increasing, and it is believed to be one of the key environmental effects that can dramatically change the star formation activity of galaxies and hence their evolution. Intriguingly however, some cases with clear signs of ram pressure stripping are found in the environment which betrays our expectations (e.g. large clustercentric distances), and our understandings to the detailed working principle behind ram pressure stripping seem to be still lacking. As one of the ways to gain more theoretical insights into the conditions for ram pressure stripping process, we have been comparing the gas truncation radius which is predicted based on the simple Gunn & Gott's prescription with what is actually observed in a sample of carefully selected Virgo galaxies. In this work, we present the results of our comparisons between the theoretically predicted truncation radius and the observationally measured truncation radius for individual galaxies in the sample and discuss which additional conditions are needed in order to fully understand the observations.

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Influence of Stripping and Counter Punching Forces on Fine Blanking Characteristics of T-shaped Products (T형 제품의 파인 블랭킹 가공 특성에 미치는 스트리핑력과 카운터 펀칭력의 영향)

  • Kim, J.H.;Ryu, J.G.;Sim, K.S.;Kim, D.H.;Chang, Y.D.;Lee, J.H.
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.6
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    • pp.15-21
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    • 1997
  • This study is performed for investigating the effects of stripping and counter punching forces on shearing characteristics in fine blanking of T-shaped products, such as camber, burr-height and dimensional accuracy, etc by experiments. Conventional hydraulic press is used for experiments so that both the stripping force and counter punching force can be arbitrarily adjusted by another hydraulic unit connected to the fine blanking die. Specimens are selected as hot rolled steel sheet and carbon steel sheet commonly used in auto- mobile company. Based on the experimental results, both the dimensional accuracy and the burr height are not influenced by the stripping and counter punching forces, wherease the camber height representing dish- shaped deflection is much influenced by them, it can be seen through this study that the finely cut surface of T-shaped blank can be obtained even in conventional hydraulic press if additional equipments and specially designed die are employed.

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A Study on Photoresist Stripping Using High Density Oxygen Plasma (고밀도 산소 플라즈마를 이용한 감광제 제거공정에 관한 연구)

  • Jung, Hyoung-Sup;Lee, Jong-Geun;Park, Se-Geun;Yang, Jae-Kyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.2
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    • pp.95-100
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    • 1998
  • A helical inductively coupled plasma asher, which produces low energy and high density plasma, has been built and investigated for photoresist stripping process. Oxygen ion density in the order of $10^{11}/cm^3$ is measured by Langmuir probe, and higher oxygen radical density is observed by Optical Emission Spectrometer. As RF source power is increased, the plasma density and thus photoresist stripping rate are increased. Independent RF bias power to the wafer stage provides a dc bias to the wafer and an ability to add the ion assisted reaction. At 1 KW of the source power, the coupling mechanism of the RF power to the plasma is changed from the inductive mode to the capacitive one at about 1 Torr. This change causes the plasma density and ashing rate decreases abruptly. The critical pressure of the mode change becomes larger with larger RF power.

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VP-ellipsis, Stripping, and the Functions of the Delimiter -to in Korean

  • Kim, So-Jee;Cho, Sae-Youn
    • Language and Information
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    • v.20 no.1
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    • pp.93-110
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    • 2016
  • VP-ellipsis constructions in English can be schematized as S + [NP finite-AUX __ ] where the underlined part is understood to be a VP. Similarly, the pattern S + NP[-to] can be observed in Korean colloquial contexts. Though the English VP-ellipsis sentence pattern and the Korean pattern superficially seem to be similar, the Korean pattern exhibits peculiar properties: Syntactically, the NP of the pattern should have the delimiter -to. Semantically, it may convey ambiguous readings: VP-ellipsis-like and/or Stripping-like interpretation. To account for the pattern at issue, we propose a base-generated analysis driven by the delimiter -to within a construction grammar. We claim that the mother of the NP[-to] in this pattern is an S whose meaning is ambiguous between a VP-ellipsis-like and a Stripping-like reading. Consequently, the code of the VP-ellipsis in English is finite auxiliary verbs while that of the pattern S + NP[-to] in Korean is the delimiter -to.

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Mercury Ion Monitoring in Mercury Plating Bath by Anodic Stripping Voltammetry

  • Park, Mijung;Yoon, Sumi;Shin, Woonsup
    • Journal of Electrochemical Science and Technology
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    • v.7 no.3
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    • pp.241-244
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    • 2016
  • Anodic stripping voltammetry (ASV) is successfully applied in mM level detection of mercury ion in an electroplating bath which is currently used in preparing a cathodic electrolyzer. Glassy carbon electrode is used for the detection and the optimum condition obtained is 10 s deposition at −1.4 V vs. Ag/AgCl and stripping by scanning from −1.4 to +0.4 V vs Ag/AgCl at 50 mV/s. By applying the method, the mercury ion concentration in the electroplating bath could be successfully monitored during the plating.

Shield Wire Stripping of Micro Coaxial Cable for Medical Device Using Laser (레이저를 이용한 의료기기용 미세 동축케이블의 실드선 탈피)

  • Lee, Jeong-Wan;Kim, Jung-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.9
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    • pp.64-71
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    • 2009
  • Recently as ultrasonic medical devices are gradually developed, many of those require smaller and more precision coaxial cables in the probe. So, the use of micro coaxial cable becomes an efficient solution for ultrasonic machine. However, there are many difficulties in stripping micro coaxial cable by traditional mechanical process. In this paper we use the Nd:YAG laser for the efficient striping of conduct wire of cable. Through some experiments, we found that there is a new possibility in the proposed method. Also, we propose a pre-process of the cable before stripping in order to enhance the performance.