• Title/Summary/Keyword: Chemical techniques

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A Study on the Engineering Properties of Micro Fine Hybrid Silicate Based Grout (마이크로 복합실리카 그라우트의 공학적 특성에 관한 연구)

  • 천병식;김진춘;최영철;정종주;신상재;이홍재
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.63-70
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    • 2000
  • In 1925, H.J. Joosten was the first in the world to use chemical injection grouts composed of sodium silicate and calcium chloride. This unique development prompted the introduction of other chemical grouting techniques. Among these chemical grouting techniques, sodium silicate based grout has been the most widely used in the world, but it has not been generally considered to be a permanent material. Therefore, studies to improve the weak points of sodium silicate based grout have been conducted, and new applications of grout were recently developed. We also developed the micro fine hybrid silicate grout of suspention type which properties are sepecialized as the high strength and durability, according to the reactant of special sodium silicate grout and the high strength hardener. As the results of this study we could derive the 2 times over high strength of Micro fine hybrid Silicate grouting method(MS method) more than that of the ordinary sodium silicate grout. And also we could confirm that the alkali leakage of micro fine hybrid silicate grout is less than that of ordinary sodium silicate grout. So we could get the high strength and durability of hybrid silicate grout are superior to those of ordinary sodium silicate grout.

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Current Status of Heat Capacity Measurement Techniques for Ionic Liquids by DSC (DSC를 이용한 이온성 액체 열용량 측정 기술 현황)

  • Jo, Ye Lim;Kim, Ki-Sub;Park, Byung Heung
    • Journal of Institute of Convergence Technology
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    • v.4 no.1
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    • pp.5-8
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    • 2014
  • Recently ionic liquids received much attention as novel materials capable of replacing traditional solvents. The applicability of the ionic liquids should be determined based on their physico-chemical properties. Heat capacity is one of the most important properties to be considered when a process is developed using the ionic liquids and currently DSC has been proved as an effective technique to measure the heat capacity. Micro DSCII can measure heat capacities of various liquids by both an isothermal step method and a scanning method. DSC Q100 and MDSC are able to measure heat capacities of several ionic liquids. For each ionic liquid linear regression of the heat capacity as a function of temperature has been performed to increase accuracy. To investigate the feasibility of ionic liquids as PCMs, their heat capacities have been measured by using Pysis I DSC. This paper briefly summarizes the present techniques of measuring heat capacities of ionic liquids by DSC.

Novel Techniques for Remediation of Contaminated Soil with Heavy Metals Using Magnetic Substances (자성체를 사용하는 중금속 오염토양의 새로운 복원기술)

  • Jeon, Choong
    • Journal of the Korea Organic Resources Recycling Association
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    • v.19 no.4
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    • pp.90-96
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    • 2011
  • In order to remediate contaminated soils with heavy metals, many techniques have been developed and proposed. However, weakness for the various techniques has been making application for actual process difficult. They have been led to the necessity for novel techniques. Therefore, in this study, novel techniques which are developing and commercializing recently in domestic/foreign country will be introduced, especially it will be focused on remediation technique for contaminated soil with heavy metals using magnetic material.

A Study on Process Integrated Innovation System for a LNG Industry (휘발성 유기화합물의 배출량 산정 및 관리 소프트웨어 개발)

  • Yi Jonghyeop;Park Hyeonsoo;Lee Sunwoo;Kim Hwayong
    • Journal of the Korean Institute of Gas
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    • v.7 no.2 s.19
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    • pp.7-13
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    • 2003
  • Abstract This paper presents new emission mechanism and emission estimation model in volatile organic compounds(VOCs) emission sources. Also classifies applicable emission reduction techniques and presents new economical evaluation method for each techniques. We ultimately developed VEER(VOCs Emission Estimation and Reduction) software, which is backed by above mentioned model, emission source DB, Chemical properties DB, meteorological DB, and emission factor DB. With VEER, users in enterprise, central government and local self-governing body can get reliable emission results easily, and choose suitable emission reduction techniques.

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Recent Trends and Prospects of Chemical Enhanced Oil Recovery (석유회수증진을 위한 화학적 공법 연구 동향 및 전망)

  • Choi, Youngil;Kang, Pan-Sang;Lim, Jong-Se
    • Journal of the Korean Society of Mineral and Energy Resources Engineers
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    • v.55 no.6
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    • pp.660-669
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    • 2018
  • Enhanced oil recovery (EOR) is a method used to improve the recovery factor of remaining hydrocarbon in reservoir. Polymer and surfactant EOR techniques have limitations depending on reservoir or production conditions (temperature, salinity, etc.) because the polymer and surfactant are highly affected by the reservoir conditions. In this study, analysis of the current improvements to chemical substances and application technologies was performed based on recent research data. Conventional polymer is readily degraded by the conditions of high temperature and high salinity. Therefore, new polymers and injection techniques have been developed to remediate such problems. In addition, surfactant applicable to shale and carbonate reservoirs is developed as petroleum recovery expands to unconventional reservoirs. However, these chemical substances are not widely used in the current oil fields due to high costs. Therefore, further studies must be conducted to reduce the cost and thus increase the effectiveness of EOR techniques.

Complete Assignment of the $^H1$ and $^{13}C$ NMR Spectra of a Sucrose Ester from Euphorbia Lathyris L.

  • Jung, Min-Hwan;Kim, Hyun-Sik;Sangdoo Ahn;Kim, Cheong-Taek;Jin, Mu-Hyun;Yim, Yong-Hyeon;Kim, Young-Kook;Jong hoa Ok
    • Journal of the Korean Magnetic Resonance Society
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    • v.4 no.2
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    • pp.125-132
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    • 2000
  • The detailed $^1$H and $^{13}$ C NMR assignments of a novel sucrose isovaleryl ester isolated from the seed of Euphorbia Lathyris L., were achieved by one-and two-dimensional techniques. The new sucrose ester was characterized as an $\alpha$-D-glucopyranoside, 3,4,6-tris-O-(3-methyl-1-oxobutyl)-$\beta$-D-fructofuranosyl, 2,6-bis(3-methylbutanoate); sucrose 4,7,8,11,12-pentaisovalerate by MS and NMR experiments.

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Characteristics of protein extracted from oyster shell (굴의 패각으로부터 추출된 단백질의 특성연구)

  • Lee, Seung-Woo;Sin, Na-Yeong;Choe, Cheong-Song
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.37-40
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    • 2001
  • We showed the result that an appreciable difference of secondary structures in the intracrystlline protein was observed between Normal and Deform shells. In order to understand the exact secondary structure of proteins, we investigated the changes in protein conformation from the specific layers via Fourier Self-Deconvolution(FSD) techniques, using ATR(Attenuated Total Reflection) information.

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Rheometry of complex fluids

  • Mewis, Jan;Moldenaers, Paula
    • Korea-Australia Rheology Journal
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    • v.11 no.4
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    • pp.313-320
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    • 1999
  • The difficulties involved in measuring rheological characteristics of complex fluids are discussed. Possible measurement errors, related to the complex nature of the sample, are reviewed. They are explained in terms of the various physical and chemical mechanisms that can cause them. This leads to possible strategies and techniques for avoiding measurement errors and for obtaining useful structural information from rheological experiments on complex materials. Finally, future evolutions in rheometry are discussed.

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Chromatographic Techniques for the Isolation and Purification of Metalloporphyrins from Crude Asphalts (크로마토그래피를 이용한 아스팔트로 부터 금속 포르피린의 분리및 정제)

  • Woo Ki Chae
    • Journal of the Korean Chemical Society
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    • v.28 no.6
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    • pp.393-398
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    • 1984
  • Porphyrin-rich materials were obtained from some crude asphalts by gel permeation chromatography and silica gel chromatography. After extraction of each chromatographic fractions through alumina with pyridine, more concentrated metalloporphyrins were obtained. Demetallation of metalloporphyrins was possible without destroying porphyrin ring to provide different type of metal free porphyrins.

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Comparison of Low Concentration and High Concentration Arsenic Removal Techniques and Evaluation of Concentration of Arsenic in Ground Water: A Case Study of Lahore, Pakistan

  • Yasar, Abdullah;Tabinda, Amtul Bari;Shahzadi, Uzma;Saleem, Pakeeza
    • Korean Chemical Engineering Research
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    • v.52 no.5
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    • pp.620-626
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    • 2014
  • The main focus of this study was the evaluation of arsenic concentration in the ground water of Lahore at different depth and application of different mitigation techniques for arsenic removal. Twenty four hours of solar oxidation gives 90% of arsenic removal as compared to 8 hr. or 16 hr. Among oxides, calcium oxide gives 96% of As removal as compared to 93% by lanthanum oxide. Arsenic removal efficiency was up to 97% by ferric chloride, whereas 95% by alum. Activated alumina showed 99% removal as compared to 97% and 95% removal with bauxite and charcoal, respectively. Elemental analysis of adsorbents showed that the presence of phosphate and silica can cause a reduction of arsenic removal efficiency by activated alumina, bauxite and charcoal. This study has laid a foundation for further research on arsenic in the city of Lahore and has also provided suitable techniques for arsenic removal.