• 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.

• Membrane and Water Treatment
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• 제8권2호
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• pp.185-199
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• 2017

Low-pressure membrane filtration is increasingly used for tertiary treatment of wastewater effluent organic matter (EfOM), mainly comprising organic base/neutral compounds. In-line coagulation with underdosing, charge neutralization, and sweep floc conditions prior to ultrafiltration (UF) was studied to determine removals of the EfOM components and consequent reduction of fouling using polyethersulfone membranes. Coagulation and UF substantially reduced fouling for all coagulation conditions while removing from 7 to 38% of EfOM organic acids. From 7 to 16% of EfOM organic base/neutrals were removed at neutral pH but there was no significant removal for slightly acid coagulation conditions even though fouling was substantially reduced. Sweep floc produced the lowest resistance to filtration but may be inappropriate for in-line use due to the large added volume of solids. Charge-neutralization resulted in poor recovery of the initial flux with hydraulic cleaning. Under-dosing paralleled sweep floc in reducing hydraulic resistance to filtration (for sub-critical flux) and the initial flux was also easily recovered with hydraulic cleaning. Hydrophobic and hydrophilic base/neutrals were identified on the fouled membranes but as previously reported the extent of fouling was not correlated with accumulation of organic base/neutrals.

• 유기물자원화
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• 제2권1호
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• pp.41-49
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• 1994

이 연구는 한국잔디(Zoysia matrella L. Merr.)에 미치는 유기질비료의 효과와 토양의 화학적 특성을 조사하기 위하여 수행되었다. 연구결과는 다음과 같이 요약된다. 1. 유기질 비료는 한국잔디(Zoysia matrella L. Merr.)의 잔디포를 조성할 때 기비로 적합하였다. 2. 잔디의 엽록소 함량은 유기질 비료 단용구보다 복합비료(N:P:K = 21:17:17) 및 유기질비료의 혼용구에서 더욱 많았다. 3. 토양중 유효인산의 함량은 유기질 비료의 사용으로 증대되었다. 4. 잔디와 건물중을 무처리구에 비하여, 기비처리구는 약 40%, 추비처리구는 약 12%의 중수효과를 나타내어 유기질비료의 사용은 기비처리가 추비처리보다 효과적이었다.

• Nano
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• 제13권11호
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• pp.1850132.1-1850132.14
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• 2018

The direct synthesis of metal-organic frameworks (MOFs) with acidic and basic active sites is challenging due to the introduction of functional groups by post-functionalization method often jeopardize the framework integrity. Herein, we report the direct synthesis of acid-base bifunctional MOFs with tuning acid-base strength. Employing modulated hydrothermal (MHT) approach, microporous MOFs named $UiO-66-NH_2$ was prepared. Through the ring-opening reaction of 1,3-propanesultone with amino group, $UiO-66-NH_2-SO_3H-type$ catalysts can be obtained. The synthesized catalysts were well characterized and their catalytic performances were evaluated in one-pot glucose to 5-HMF conversion. Results revealed the acid-base bi-functional catalyst possessed high activity and excellent stability. This work provides a general and economically viable approach for the large-scale synthesis of acid-base bi-functional MOFs for their potential use in catalysis field.

• 약학회지
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• 제9권1_2호
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• pp.14-17
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• 1965

It has been known that the organic base complexes formed with the anionic acid base indicators are highly soluble in non-polar solvents but relatively insoluble in water. In the work reported here the formation of the complex between chloropromazine and bromothymol blue was studied and applied it to the determination of the base. The values to determine the binding ratio of the base with the indicator at pH 3.5 obtained from the application of Job's method of continuous variation and mol ratio method were both 1:1. From the application of this reaction to the determination of the base with carbon tetrachloride as the solvent for the extraction, fairy good results have been obtained.

• 상하수도학회지
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• 제25권6호
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• pp.861-867
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• 2011

Wastewater from crude oil reserve base usually contains large amount of non-biodegradable contaminants. The conventional wastewater treatment progress can hardly meet the regulation of wastewater effluent quality. This study investigated the removal of non-biodegradable organic contaminants in wastewater from crude oil reserve base using a pulse UV treatment. The modified process incorporating pulse UV process was set up to treat the wastewater from crude oil reserve base. The treatment process is composed with coagulation and flocculation, micro-bubble flotation, sand filter, pulse UV system, and GAC filter. The results show CODMn was effectively removed by the process with pulse UV system and it can meet the wastewater effluent regulation. The single effect of pulse UV process in CODMn removal was not significant(9~15% based on sand filtered effluent), however with the subsequent activated carbon filter the removal ratio CODMn was increased up to 28% compared to the process without pulse UV syetem.

• Journal of Information Display
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• 제13권2호
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• pp.67-71
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• 2012

In today's mobile world, small and lightweight information systems are becoming increasingly important. Microdisplays are the base for several near-to-eye display devices. The addition of an integrated image sensor significantly boosts the range of applications. This paper describes the base-building block for these systems: the bidirectional organic light-emitting diode microdisplay. A small and lightweight optic design, an eye-tracking algorithm, and interaction concepts are also presented.

• 한국염색가공학회지
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• 제22권3호
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• pp.181-186
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• 2010

A thermoresponsive poly(NIPAM-co-dye) labeled with benzopyran-based D-$\pi$-A type dye was prepared by typical radical copolymerization. It can be also constructed a acid/base-induced molecular switch by modulation of intramolecular charge transfer with protonation/deprotonation. The lower critical solution temperature behavior was investigated by means of UV-vis spectroscopy which allows the measurement of the phase transition from $25^{\circ}C$ to $45^{\circ}C$ in aqueous DMSO solution. The morphology of the internal microstructure of the poly(NIPAM-co-dye) hydrogel was observed by scanning electron microscopy. The reversible switch could be obtained by thermal and acid/base stimuli.

• Geomechanics and Engineering
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• 제12권6호
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• pp.899-917
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• 2017

Sixty four tests were performed in a steel tank to investigate the axial responses of piles driven into organic soil prepared at two different densities using a drop hammer. Four different pile materials were used: wood, steel, smooth concrete, and rough concrete, with different length to diameter ratios. The results of the load tests showed that the shaft load capacity of rough concrete piles continuously increased with pile settlement. In contrast, the others pile types reached the ultimate shaft resistance at a settlement equal to about 10% of the pile diameter. The ratios of base to shaft capacities of the piles were found to vary with the length to diameter ratio, surface roughness, and the density of the organic soil. The ultimate unit shaft resistance of the rough concrete pile was always greater than that of other piles irrespective of soil condition and pile length. However, the ultimate base resistance of all piles was approximately close to each other.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3640-3644
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• 2012

An efficient synthetic method for direct Henry reaction catalyzed by a biguanide; namely metformin, as an organosuper-base, between a variety of aromatic and aliphatic aldehydes and nitromethane under neat conditions has been developed. Convenient procedure for removal of the catalyst, chemoselective acquiring of ${\beta}$-nitroalcohols as predominant products, as far as possible short reaction time with excellent conversions are advantages of the developed protocol.