• Archives of Pharmacal Research
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• 제7권1호
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• pp.23-31
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• 1984

An improved mass spectrometric method for multicomponent analysis of metabolites in urine, well-suited for clinical biochemistry, is described. The method involves solvent elution of the metabolites from an adsorbent and the concentration of the eluate on a microadsorption column. This is administered by a direct inlet probe into the ionizing source of field ionization mass spectrometry (FIMS), which yield a molecular weight profile of the metabolites. The procedure provides rapidly (within one hour) reproducible profiles from a small volume of urine. The optimization of the sampling technique and the reproducibility are discussed.

• 한국대기환경학회지
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• 제9권1호
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• pp.101-106
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• 1993

In order to separate the Freon-12 and air mixture$(CF_2Cl_2/Air=0.1/99.9 vol.%)$ by pressure swing adsorption (PSA), the breakthrough curve was experimentally observed in a fixed bed adsorption column. A single adsorber was packed with various adsorbents such as, the activated carbon(S-AC, W-AC) and the molecular sieve(MS-5A, MS-13X). The order of appearance of breakthrough curve is MS-5A > MS-13X > W-AC > S-AC. The activated carbon was found to be more effective adsorbent for separating Freon-12 from the mixture than the molecular sieve was. From the experimental data obtained by the separation of Freon-12 gas out of the air stream in the steady-state PSA process cycle, whose size is the same one of column used for the breakthrough curve observation, it has been confirmed that Freon-rich gas could be obtained from the purge step of PSA and Freon-free air could be obtained from the adsorption step of PSA cycle.

• 한국환경과학회지
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• 제23권6호
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• pp.1143-1149
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• 2014

The adsorption experiments of lithium ions were conducted in the fixed bed column packed with activated carbon modified with nitric acid. Effect of inlet concentration, bed hight and flow rate on the removal of lithium ions was investigated. The experimental results showed that the removal and the adsorption capacity of lithium ions increased with increasing inlet concentration, and decreased with increasing flow rate. When the bed height increased, the removal and the adsorption capacity increased. The breakthrough curves gave a good fit to Bohart-Adams model. Adsorption capacity and breakthrough time calculated from Bohart-Adams model, these results were remarkably consistent with the experimental values. The adsorption capacity was not changed in the case of 3 times repetitive use of adsorbent.

• 분석과학
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• 제12권3호
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• pp.196-202
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• 1999

갈조류인 Sargassum horneri를 중금속 흡착제로 사용하여 중금속 Cd(II) 및 Pb(II)이온을 제거하였다. Sargassum horneri는 동해안에서 채취하였고, 풍건 건조시켜 40~60 mesh의 입자 크기로 흡착제를 만들어 사용하였다. batch법은 진탕 시간에 따른 흡착량을 측정함으로써 흡착속도를 조사하였고, column법은 해조 분말을 충진 시킨후 일정농도의 중금속용액을 1 mL/min의 속도로 흘려보내면서 흡착시키고 흡착량을 알아 보았다. 중금석 흡착에 미치는 pH의 영향은 batch법과 column법 모두, pH 10.5>7.0>3.5순으로 나타났다. Pb(II)이온이 Cd(II)이온보다 높은 흡착량을 보였다. 특히 batch법에서는 모든 pH의 조건하에서 5분이내에 최대 흡착량에 도달하였다. 회수율은 batch법에 의해 흡착된 중금속의 회수율이 column법에 의해 흡착된 중금속의 회수율 보다 조금 높게 나타났다.

• 아시안잔디학회지
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• 제20권1호
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• pp.47-55
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• 2006

본 실험은 농약 흡착제(adsorbent)로서 입상 활성탄(활성탄 I 및 활성탄 II) 및 차콜의 사용가능성을 알아보기 위하여 흡착질(adsorbate)로 현재 골프장에서 사용하고 있는 살충제인 스미치온(Fenitrothion)과 살균제인 호리쿠어(Tebuconazole)를 대상으로 하였다. 흡착실험에서는 스미치온 및 호리쿠어의 처리 농도별 흡착에 미치는 영향과 흡착제의 입자크기가 흡착에 미치는 영향을 살펴본 결과, 흡착실험에서는 흡착제의 입자 크기가 작을수록 높은 흡착율을 보였으며, 활성탄이 차콜에 비하여 상대적으로 높은 흡착율을 나타내었다. 그러나 스미치온의 탈착(desorption)에 관한 실험에서는 활성탄 및 차콜 모두 1200mm 이상의 강우량에서도 스미치온이 용탈되지 않았으므로, 차콜 또한 활성탄과 함께 골프장 농약 흡착제로서의 이용 가능한 것으로 나타났다.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.321-326
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• 2009

간단한 기체농도 측정장치를 제안하여, 혼합기체를 분리하는 흡착공정에서 성능을 실험적으로 조사하였다. 측정센서는 수정진동자의 전극에 고체의 흡착제를 도포하여 유효성분을 선택적으로 분리하게 하여 농도를 측정하였다. 센서용 흡착제는 마이크로 입자의 카본 크라이오젤(Micro-Particle Carbon(MCC))을 사용하였고, 공기와 i-부탄의 혼합기체를 대상으로 대나무 활성탄을 채운 칼럼에서 분리하는 공정을 사용하였다. 칼럼의 입구와 출구에 측정시스템을 각각 장치하고 i-부탄의 농도를 측정하였다. 입구와 출구의 실제농도를 GC로 측정한 결과와 측정한 수정진동자의 공진주파수를 비교하여 제안한 측정시스템이 유용하게 농도를 측정할 수 있음을 보였다. 실험을 통하여 제안하는 시스템이 비교적 간단한 장치로, 실시간 인라인 측정이 가능함을 입증하여 실제공정에 유용하게 활용할 수 있음을 보였다.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2384-2393
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• 2018

Porous alginate-based hydrogel beads (porous ABH) have been prepared through a facile and sustainable template-assisted method using nano-calcium carbonate and nano-$CaCO_3$ as pore-directing agent for the efficient capture of methylene blue (MB). The materials were characterized by various techniques. The sorption capacities of ABH towards MB were compared with pure sodium alginate (ABH-1:0) in batch and fixed-bed column adsorption studies. The obtained adsorbent (ABH-1:3) has a higher BET surface area and a smaller average pore diameter. The maximum adsorption capacity of ABH-1:3 obtained from Langmuir model was as high as $1,426.0mg\;g^{-1}$. The kinetics strictly followed pseudo-second order rate equation and the adsorption reaction was effectively facilitated, approximately 50 minutes to achieve adsorption equilibrium, which was significantly shorter than that of ABH-1:0. The thermodynamic parameters revealed that the adsorption was spontaneous and exothermic. Thomas model fitted well with the breakthrough curves and could describe the dynamic behavior of the column. More significantly, the uptake capacity of ABH-1:3 was still higher than 75% of the maximum adsorption capacity even after ten cycles, indicating that this novel adsorbent can be a promising adsorptive material for removal of MB from aqueous solution under batch and continuous systems.

• 한국물환경학회지
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• 제26권3호
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• pp.454-459
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• 2010

This study investigated the applicability of manganese coated media such as manganese coated sand (MCS), manganese coated sericite (MCSe) and manganese coated starfish material calcined at $550^{\circ}C$ (MCSf) to remove Mn(II) in synthetic wastewater. Manganese coated media prepared at different pH was applied in the treatment of soluble Mn(II) in batch and column experiments at various Mn(II) concentrations. The amount of Mn coated on three different media was approximately 800~1100 mg/kg. From the stability test, negligible dissolution of Mn was observed above pH 3.0. In batch test, more than 40% of Mn(II) was removed by all sand media at various manganese concentrations. In order to see the effect of additional oxidant for the removal of Mn(II), 4 mg/L of hypochlorite was added in Mn(II) solution during column experiment. Breakthrough of Mn(II) was greatly retarded in the presence of hypochlorite in all column reactors packed with different media. Among the manganese coated media, MCSf prepared at pH 4 indicated the highest removal capacity. The removal efficiency of Mn(II) was also increased in the multi-layer system (0.5 g of MCS, MCSe, and MCSf each).

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1125-1129
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• 2004

This work assesses the potential of natural Analcime Zeolite as an adsorbent for preconcentration of lead (II) traces. Lead is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol by column method with Analcime in the pH range of 5-6.5 and 2 mL $min^{?1}$ flow rate. Lead was removed from the column with 10.0 mL of 4 M hydrochloric acid and was determined by anodic stripping differential pulse voltammetry. 0.5ppb detection limit was obtained and linear dynamic range was 3 to $1.2{\times}10^5$ ppb in final solution with correlation coefficient of 0.999 and relative standard deviation of ${\pm}$ 1.2% (for eight replicate determination of 2.5 ${\mu}g\;mL^{?1}$ of lead). Various parameters such as the effect of pH, flow rate, instrumental conditions and interferences of some ions on the determination of lead have been studied in detail for optimization of conditions. The method was successfully applied for determination of lead in various samples.

• 한국재료학회지
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• 제32권1호
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• pp.36-43
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• 2022

Breakthrough analysis has widely been explored for the dynamic separation of gaseous mixtures in porous materials. In general, breakthrough experiments measure the components of a flowing gas when a gaseous mixture is injected into a column filled with an adsorbent material. In this paper, we report on the design and fabrication of a breakthrough curve measurement device to study the dynamic adsorptive separation of hydrogen isotopologues in porous materials. Using the designed system, an experiment was conducted involving a 1:1 mixture of hydrogen and deuterium passed through a column filled with zeolite 13X (1 g). At room temperature, both hydrogen and deuterium were adsorbed in negligible amounts; however, at a temperature of 77 K, deuterium was preferentially adsorbed over hydrogen. The selectivity was different from that in the existing literature due to the different sample shapes, measurement methods, and column structures, but was at a similar level to that of cryogenic distillation (1.5).