• Elastomers and Composites
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• 제54권3호
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• pp.188-200
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• 2019

Rubber articles contain various organic additives such as antidegradants, curing agents, and processing aids. It is important to extract and analyze these organic additives. In this paper, various extraction methods of organic additives present in rubber composites were introduced (solvent extraction, Soxhlet extraction, headspace extraction, and solid-phase microextraction), and the extracts were characterized using gas chromatography/mass spectrometry (GC/MS). Solvent and Soxhlet extractions are easy-to-perform and commonly used methods. Efficiency of solvent extraction varies according to the type of solvent used and the extraction conditions. Soxhlet extraction requires a large volume of solvent. Headspace sampling is suitable for extracting volatile organic compounds, while solid-phase extraction is suitable for extracting specific chemicals. GC/MS is generally used for characterizing the extract of a rubber composite because most components of the extract are volatile and have low molecular weights. Identification methods of chemical structures of the components separated by GC column were also introduced.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.189-194
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• 1999

The antiwear performance of several organic phosphates ,such as tricrecylphosphate(TCP), tributylphosphate(TBP), diphenylhydrogenphosphate(DPHP) ,dissolved in polyol ester based oils is studied. These organic phosphates are well known for antiwear additive for lubricating oil that produce reacted surface protective film. These antiwear additives can drastically reduce wear with their concentration increasing, because the amount of additive adsorbed on metal sur(ace increases. But in the higher concentration region, the wear is increased by excessive and corrosive reaction of the metal surface with these additives. That is to say, there is an optimum concentration for minimum wear. The optimum concentration was different with the kinds of base oils and additives. Different polyolesters showed different optimum concentrations of the additive. The order of optimum concentration among the polyolesters was different with different phosphates. The order of the optimum concentration is shown that the effect of the concentration of additives on the antiwear performance. It can be explained by the interaction between additives and base oils using the solubility parameter.

• Tribology and Lubricants
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• 제19권3호
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• pp.159-166
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• 2003

This research for replacement of chlorine or sulfur based EP(extreme pressure) -additives which is restricted materials by environmental regulation. The subject of this study is as follows, 4-ball test and friction coefficient test were experimented in accordance with temperature and velocity, compounding with several organic or inorganic metallic elements. After 4-ball test, wear area of steel ball was analysed by SEM-EDX. As the analysis, organic and inorganic elements make a effect for extreme pressure lubricity. It is shown that the friction coefficient of lubricant which includes chlorine or sulfur additives, the scoring phenomenon is found accord-ing to temperature and the scuffing phenomenon at 200$^{\circ}C$. Applying to Na, P, S, Zn, Ca based on inorganic and organic elements, the result showed that friction coefficient is decreased more and more, as increasing temperature of lubricant. The additive based on S, Cl, P elements is effect far extreme pressure in the sample#1 and Na, P, S, Zn, Ca in sample #2. These elements are environmental contaminants and S, Cl based on EP additives which are very popular in domestic industry, when they are properly composed with non-chlorine based on additives and Na, P, S, Zn, Ca organic or inorganic elements. It is showed that lubricity and excellent anti-wear properties.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 추계학술대회 논문집
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• pp.90-92
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• 2003

Effects of organic additives on YBCO coated conductor prepared by MOD-TFA method were investigated. YBCO thin films were deposited on (100)-oriented single crystalline LaAlO$_3$substrates by conventional MOD-TFA process. The microstructures of YBCO thin films show labyrinth-like patterns. The origin of this microstructure was delineated by compositional inhomogeneity during the pyrolysis process of MOD process and it was shown that organic additives changes the microstructure and texture development of grown YBCO films

• 한국응용과학기술학회지
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• 제33권4호
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• pp.734-740
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• 2016

The micron-sized indium zinc tin oxide (IZTO) particles were prepared by spray pyrolysis from aqueous precursor solution for indium, zinc, and tin and organic additives such as citric acid (CA) and ethylene glycol (EG) were added to aqueous precursor solution for indium, zinc, and tin. The obtained IZTO particles prepared by spray pyrolysis from the aqueous solution without organic additives had spherical and filled morphologies, whereas the IZTO particles obtained with organic additives had more hollow and porous morphologies. The micron-sized IZTO particles with organic additives were changed fully to nano-sized IZTO particles, whereas the micron-sized IZTO particles without organic additives were not changed fully to nano-sized IZTO particle after post-treatment at $700^{\circ}C$ for 2 hours and wet-ball milling for 24 hours. Surface resistances of micron-sized IZTO's before post-heat treatment and wet-ball milling were much higher than those of nano-sized IZTO's after post-heat treatment and wet-ball milling. From IZTO with composition of 80 wt. % $In_2O_3$, 10 wt. % ZnO, and 10 wt. % $SnO_2$ which showed a smallest surface resistance IZTO after post-heat treatment and wet-ball milling, thin films were deposited on glass substrates by pulsed DC magnetron sputtering, and the electrical and optical properties were investigated.

• 한국자기학회지
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• 제15권3호
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• pp.198-201
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• 2005

전기도금 방법으로 제작된 니켈과 니켈-구리 합금박막에 미치는 유기첨가제(organic additive)의 영향을 조사하였다. 유기첨가제를 가하여 도금하는 니켈 박막의 경우 순수한 전해액만을 이용하여 도금한 박막과는 다른 결정성을 갖는다 도금조건을 일정하게 한 후 니켈-구리의 합금 박막용 전해액에 유기첨가제를 가하면 구리와 니켈의 조성비율이 변화하는데 유기첨가제의 성분과 농도에 따라 니켈의 함유율이 $65\~95\%$ 영역에서 조절이 가능하다. 유기첨가제에 의한 이러한 물성의 변화는 자성의 변화를 유도하여 도금 박막의 자기저항의 증가와 감소에도 기여하는 것으로 나타났다.

• Preventive Nutrition and Food Science
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• 제14권3호
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• pp.220-225
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• 2009

In this study, the color value, water solubility, swelling power and sensory evaluation of Dioscorea batatas was examined with the addition of functional additives such as sugar alcohols and organic acids to investigate the browning inhibition and preference of these additives. Treatment with erythritol and citric acid were found to result in the highest hunter L-value, solubility and swelling power relative to the other functional additives. Therefore, erythritol and citric acid were selected as additives for Dioscorea batatas. The Dioscorea batatas containing the mixed additives (erythritol and citric acid) showed higher brightness, water solubility and swelling power than those containing only a single additive. In addition, the color and taste preference determined in the sensory evaluation had higher values when the mixed additives were used.

• 한국응용과학기술학회지
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• 제31권4호
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• pp.694-702
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• 2014

마이크론 크기를 가지는 ITO(indium tin oxide) 입자들은 인듐과 틴의 수용성 전구체들과 유기 첨가제를 분무 열분해하여 얻었다. 유기 첨가제로서는 에틸렌글리콜과 시트르산을 이용하였다. 분무 열분해 시 에틸렌글리콜과 시트르산과 같은 유기첨가제를 첨가하지 않고 얻어진 ITO 입자들은 구형이며 속이 꽉찬 형태를 가지는데 비해 유기 첨가제를 첨가하여 분무 열분해를 하면 얻어지는 ITO 입자들은 유기 첨가제의 양이 증가 할수록 껍질이 얇고 다공성이 증대된 중공 입자가 얻어진다. 유기첨가제를 첨가하지 않고 분무 열분해를 통해 얻어지는 마이크론 크기를 가지는 ITO는 $700^{\circ}C$에서 두 시간 동안의 후소성과 24 시간동안의 습식 볼밀링에 의해 나노 크기의 ITO로 전환되지 않으나, 유기첨가제를 첨가하고 분무 열분해를 통해 얻어지는 마이크론 크기를 가지는 ITO는 $700^{\circ}C$에서 두 시간 동안의 후소성과 24 시간 동안의 습식 볼밀링에 의해 나노 크기의 ITO로 쉽게 전환되었다. 응집된 나노 크기의 ITO의 일차 입자의 크기를 Debye-Scherrer 식에 의해 계산하였고 ITO 입자를 압축하여 만든 펠렛의 표면저항을 측정하였다.

• 한국표면공학회지
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• 제43권1호
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• pp.1-6
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• 2010

The effect of organic additives, 1-(3-sulfoproyl)-2-vinylpyridineium hydroxide (SVH) and thiourea (TU), on the precision copper electrodeposition was investigated with optical, electrochemical and x-ray diffraction techniques. It was found that SVH played a r ole as a n accelerator and TU as an i nhibitor during the electroreduction of cupric ions in acidic Cu electroplating solution. Through electrochemical measurements, TU showed more strong interaction with cupric ions than SVH and dominated overall Cu electroplating process when both additives were present in the solution. In the case of three dimensional Cu electrodeposition on the 20 ${\mu}m$-patterned Ni substrates, SVH controlled the upright growth of Cu electrodeposits and so determined its flatness, while TU prohibited the lateral spreading of Cu in the course of pulse-reverse pulse current adaptation. With microscopic observation, we obtained the optimum organic additives composition, that is, 100 ppm SVH and 200 ppm TU during the current pulsation.

• 한국세라믹학회지
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• 제32권8호
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• pp.901-908
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• 1995

In aqueous slurry processing of silicon nitride, the interaction of dispersant and binder used as polymeric processing additives on the silicon nitride particle surface was studied to identify the effect of these processing polymeric additives on the ceramic powder processing. The adsoprtion isotherm study of anionic organic molecule as dispersant and nonionic organic molecules as binder of silicon nitricde was studied to investigate the effect of these processing organic additives on the physicochemical properties of silicon nitride particles. As anionic molecule adsorbed onto silicon nitrice surface, the IEP of silicon nitride shifted toward acidic pH and changed the stability of silicon nitride particle. However, the adsorption of binder as nonionic organic molecule onto silicon nitride surface did not changed the IEP but caused the decrease of electrostatic potentials of silicon nitride. These distinctive adsorption behaviors of organic additives on silicon nitride particles can be closely correlated to the stability of silicon nitride particles suspended in aqueous media.