• 한국응용과학기술학회지
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• 제20권4호
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• pp.341-345
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• 2003

Organic acid salt of fatty polyamide (DDDT) and acrylate of fatty carbamide (DDTCA) were synthesized as a main component for the softener. O/W type non-ionic softener (NSC) was prepared by blending DDDT and DDTCA with beef tallow, lanolin anhydride. polyoxyethylene(7) stearyl ether, and polyoxyethylene(50) oleyl ether. After treatment of NSC to all cotton fabrics, the physical properties such as tear strength, crease recovery, and flexing abrasion resistance were measured. As a result of the measurement, NSC was proved to be durable non-ionic softener with good softness.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.73-77
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• 2003

In order to predict the dynamic behaviors of uranium and cobalt in a fixed bed at various influent pH values of liquid waste, the adsorption system was regarded as multi-component adsorption between each ionic species in a solution. Langmuir isotherm parameters of each species were extracted by incorporating equilibrium data with the solution chemistry of uranium and cobalt using IAST. Prediction results were in good agreement with the experimental data, except for a high concentration and pH. Although there was some limitations in predicting the cobalt adsorption, this method may be useful in analyzing a complex adsorption system where various kinds of ionic species exist in a solution.

• 한국농공학회논문집
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• 제64권3호
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• pp.25-32
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• 2022

To understand the distribution characteristics of PM_2.5 concentration in the Saemangeum Reclamation Area and nearby areas, three points of the background area, the occurrence area, and the affected area were selected and samples were collected for each season. The chemical composition was determined. As a result of analyzing the chemical composition contained in PM_2.5, NO₃^- (7.2 ㎍/m³), SO₄^2- (4.3 ㎍/m³), NH₄+ (4.3 ㎍/m³), OC (2.5 ㎍/m³), Si (1.3 ㎍/m³) m³) and EC (0.5 ㎍/m³) seemed to be the main components, and NO₃-, SO₄^2-, NH₄⁺, which are components that form secondary particles, occupied a large proportion. The composition ratio of PM_2.5 was investigated in the order of ion component (56.8%) > Unknown (27.4%) > carbon component (11.8%) > heavy metal component (4.0%). During the PM_2.5 high concentration case days, the ionic component accounted for 90.7% during atmospheric stagnation cases, whereas the chemical composition ratio was in the order of ionic component (51.7%) > heavy metal component (41.5%) > carbon component (6.8%) during yellow dust cases. It was found that the characteristic of PM_2.5 in the Saemangeum reclaimed land and surrounding areas is mainly influenced by outside (domestic and overseas) throughout the year. Ion components accounted for the largest portion of PM_2.5 components in this area, but there were few sources of SOx and NOx emission in the Seamangeum area, which are precursors for secondary particle formation. Therefore, it is judged that most of these are generated and influenced as a secondary reaction in the atmosphere from the outside.

• 한국환경농학회지
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• 제25권1호
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• pp.1-6
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• 2006

본 연구는 산성비의 대한 장기적이고 종합적인 대책방안을 마련하기 위한 기초 자료를 제공코자 1997년부터 2003년까지 7년 동안 산성강우 현상을 중심으로 조사하였다. 강수의 연차적 산성비 강하비율은 1997년 70.0%, 1998년 56.3%, 2003년 36.4%를 나타냈으나, 강우량이 적은 1999년부터 2002년의 산성비 강하비율은 $6.9{\sim}19.2%$를 보였다. 산성우에 대한 영향 평가시 단기간에 의한 것보다 장기적인 영향으로 발생하기 때문에 산성강하물의 농도뿐만 아니라 침착량의 해석이 필요하다. 강수중 주요 이온성분의 연평균 습성침착량은 각 이온성분의 당량농도에 강수량을 곱하여 산출하였다. 각 이온 성분의 침착량을 살펴보면 음이온은 ${SO_4}^{2-}>Cl^->{NO_3}^-$순이었으며, 양이온의 경우는 ${NH_4}^+>Ca^{2+}>Na^+>Mg^{2+}>K^+$순으로 많았다. 강수 중 주요성분에 대한 상관분석 결과 pH와 강수 이온 성분중 $Ca^{2+}$와 $Na^+$성분을 제외한 모든 성분에서 부의 상관을 나타냈으며 그 외 각 성분간의 상관은 정의 상관을 나타냈다. pH와 ${SO_4}^{2-}$간의 상관계수는 -0.508로 고도의 유의성을 나타냈는데 이는 ${SO_4}^{2-}$성분이 강수중 산성도를 증가시키는 주요원인 물질중 가장 큰 역할을 하고 있음을 추정할 수 있었다. 또한 ${SO_4}^{2-}$와 ${NO_3}^-$ 이온은 $Ca^{2+},\;Mg^{2+},\;K^+,\;{NH_4}^+\;and\;Na^+$ 등 양이온과 고도의 유의성을 보였다.

• Applied Biological Chemistry
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• 제47권3호
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• pp.300-306
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• 2004

양이온 및 음이온 반응성의 고분자막 8종을 casting 법에 의하여 제조한 후 이온전극에 장착하여 다채널 맛 평가시스템의 비선택성 센서 어레이를 구성하였다. 맛 센서 어레이에 의한 전기화학계측은 전위법에 의하여 행하였으며, 이 때 센서 어레이를 구성하는 각각의 맛 센서로 측정한 전위간을 막 전위 증폭기를 거쳐 증폭한 후 다채널 A/D converter를 통하여 PC에 접속하였다. 식혜, 수정과, 감귤쥬스 등 6종 24점의 시판음료를 다채널 맛 평가시스템으로 분석한 후 각 센서의 계측신호에 대한 정규화를 행하고 주성분 분석을 행하였을 때 5종 음료군의 조합에서는 제1 주성분 및 제2 주성분의 합이 전체 데이터 변이의 $70.73{\sim}85.32%$를 설명하는 것으로 나타났으며 6종 음료군의 경우에는 제1 주성분 및 제2 주성분의 합과 제1 주성분, 제2 주성분 및 제3 주성분의 합이 전체데이터 변이의 81.46%와 89.56%를 각각 설명하는 것으로 나타났다. 3차원 공간상에 6종 음료군에 대한 계측결과를 맵핑하였을 때 이들의 구분이 가능하였으며, 5종 음료군의 조합에서는 2가지 경우에 있어 2차원 평면상에서 구분되었다.

• 한국분말재료학회지
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• 제9권5호
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• pp.346-351
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• 2002

Pure and fine, two-component titanate powders (barium titanate, calcium titanate etc.) were synthesized by an ethylene glycol method. Titanium isopropoxide and other metal ionic salts were dissolved in liquid-type ethylene glycol without any precipitation. In non-aqueous system, the amount of ethylene glycol affected the solubility and homogeneity of metal cation sources in the solution. At the optimum amount of the polymer, the metal ions were dispersed effectively in solution and a homogeneous polymeric network was formed. Most of the synthesized powders had sub-micron or nano-size primary particles after calcination and the agglomerated calcined powders were easily ground by ball milling process. All synthesized titanate powders had stable crystallization behavior at low temperature and high specific surface area after ball milling. The crystallization behavior and the microstructures of the calcined powders were affected on the ethylene glycol content.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.117-120
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• 2005

The relationship between strain and applied potential was derived for composite actuators consisting single-wall carbon nanotubes (SWNTs) and conductive polymers (CPs). During deriving the relationship, an electrochemical ionic approach is utilized to formulate the electromechanical actuation of the composite film actuator. The results show that the well-aligned SWNTs composite actuator can give good actuation responses and high actuating forces available. The actuation is found to be affected by both SWNTs and CPs components and the actuation of SWNTs component has two kinds of influences on that of the CPs component: reinforcement at the positive voltage and abatement at the negative voltage. CNT/EAP was fabricated successfully using the chemical polymerization method.

• 공학논문집
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• 제6권2호
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• pp.85-98
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• 2004

The adsorption equilibrium data for the binary gas mixture system from the pure gas adsorption data of carbon dioxide and ethylene on ZSM-5 prepared were predicted. The binary gas mixture adsorption data have been examined against predicted values by two models-the vacancy solution model(VSM) and the statistical thermodynamic model(STM), using parameters obtained from the single component isotherm. The binary gas mixture data for the carbon dioxide-ethylene system were obtained for cation exchanged forms of ZSM-5 for the gas phase carbon dioxide mole fraction of 0.752 at $37^{\circ}C$ and 1 atm. The experimental adsorption phase diagrams were obtained for carbon dioxide-ethylene on sodium form ZSM-5 synthesized. The single component adsorption isotherms for carbon dioxide and ethylene were also obtained for this zeolite. The single component data were used to obtain parameters derived in two models. These parameters were, in turn, used to predict the binary mixture isotherms for this zeolite. Both the vacancy solution and the statistical thermodynamic models give satisfactory predictions of adsorption phase diagrams for the binary gas mixtures of carbon dioxide and ethylene on sodium exchanged ZSM-5. Also the correlation between the experimental data and the predicted values is generally in good agreement. The system appears to show ideal behavior with a relatively constant separation factor. The slight increase in adsorption capacity with an increase in ionic radius is due, in part, to the higher polarizability associated with larger cations.

• Journal of Electrochemical Science and Technology
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• 제2권2호
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• pp.63-67
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• 2011

To examine the effects of a two-cation ionic liquid as an electrolyte component of a supercapacitor, 1,4-bis(3-methylimidazolium-1-yl)butane tetrafluoroborate ($MIBBF_4$), dissolved in propylene carbonate (PC) or acetonitrile (ACN), is newly synthesized and tested here for potential use as an electrolyte of capacitor. The $MIBBF_4$ salt exhibits higher ionic conductivity in ACN than in PC. The supercapacitive properties of capacitors containing an activated carbon electrode and various electrolytes are evaluated using cyclic voltammetry and electrochemical impedance spectroscopy. The capacitor adopting the $MIBBF_4$/ACN electrolyte shows the largest specific capacitance at low scan rates, whereas the capacitor adopting the 1-ethyl-3-methylimidazolium tetrafluoroborate $(EMIBF_4)$/ACN electrolyte shows the largest specific capacitance at high scan rates.

• Journal of Korean Society for Atmospheric Environment
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• 제22권E1호
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• pp.27-34
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• 2006

Although the importance of size-resolved raindrops study has been known, it has not been popularized up to the present. In the present study, an attempt was made to generalize the size-resolved raindrops study by a combination of the frozen raindrop collection method and a commercially available high-performance capillary electrophoresis (HPCE). Samplings were carried out at Kyoto, Japan in October 2002. The inorganic ions (chloride, nitrate, sulphate, calcium, ammonium, sodium, magnesium, potassium) in size classified raindrop samples were successfully analyzed by HPCE with good repeatability. To assure the accuracy and precision of HPCE data, t-test was conducted with paired analytical data, which were experimentally constructed by analyzing standard solutions with HPCE and IC, respectively. T-test showed that there is no notable difference between the concentrations determined by the two analytical methods. Every ionic concentration in both cation and anion was found to be strong raindrop size dependence. Though there was slight increase of sodium and sulphate concentrations between 0.85 mm and 1.15 mm raindrop radius, it showed a strong decrease for every ionic component with increasing droplet radius. The combination of the frozen raindrop collection method and a commercially available HPCE can meet the need of size-resolved raindrops study.