• Journal of the Korean institute of surface engineering
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• v.47 no.3
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• pp.116-120
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• 2014

The addition of cyclo propane carbonyl (cpc) to chromium electroplating bath resulted in a chromium deposit which had greatly improved mechanical properties compared to conventional chromium deposits in condition of heat treatment at high temperature. The as-deposited layers had a Vicker's hardness of about 1170, which is comparable to that of conventional chromium plating deposits. With annealing, the hardness goes through a maximum of 1650 at $600^{\circ}C$. Generally speaking, the hardness of conventional plating decreases monotonically with heat treatment. X-ray diffraction show that annealing up to above $400^{\circ}C$ causes formation and growth of chromium crystallites and that chromium carbides form at above $500^{\circ}C$ temperature.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.873-877
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• 2004

The relationship between the behaviors of c.c.lipase back-extraction and their percolation phenomena by using AOT reverse micellar systems (RVMS) has been studied by the addition of a small amount of additives to organic phase such as thiols and nonionic-surfactants focusing on micelle-micelle interactions. The values of ${\beta}_t$ defined by the variation of percolation processes and back-extraction behaviors of c.c.lipase have a good linear correlation. The hydrophobicity of additive molecules suppressing the cluster formation of reverse micelles (high values of ${\beta}_t$) improved the back-extraction behavior of c.c.lipase. The back-extraction fraction and its rate of c.c.clipase are increased with decreasing of the value of hydrophilic lipophilic balance (HLB) and increasing of the hydrophobicity per additive molecules added to reverse micellar systems (RVSM) in the same additives concentration.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06b
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• pp.129-153
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• 1996

In aqueous slurry processing of silicon nitride, the interaction of dispersant and binder on the surface of particles was studied to identify the effect of these additives on ceramic powder processing. Polymethacrylic acid (PMAA) and polyvinyl alcohol (PVA) were used as dispersant and binder, respectively. the adsorption isotherms of PMAA and PVA for the silicon nitride suspension were determined, while the adsorption of PMAA was differentiated in the mixed additive system by ultraviolet spectroscopy. These experiments were done in order to investigate the effect of these organic additives on the physicochemical properties of silicon nitride suspensions. The electrokinetic behavior of silicon nitride was subsequently measured by electrokinetic sonic amplitude (ESA). As PMAA adsorbed onto silicon nitride, the isoelectric point (pHicp) shifted from pH=6.7 to acidic pH, depending on the surface coverage of PMAA. However, adsorption of PVA did not change the pHicp of suspensions, but did decrease the surface potential of silicon nitride moderately. The rheological behavior of silicon nitride suspensions was measured to assess the stability of particles in aqueous media, and was correlated with the electrokinetic behavior and adsorption isotherm data for silicon nitride.

• Tribology and Lubricants
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• v.16 no.3
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• pp.173-181
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• 2000

Friction, wear and corrosion characteristics of various MoS$_2$ bonded film lubricants were investigated to apply them to automotive wheel joints. MoS$_2$ bonded film lubricants were formulated by combinations of several additives and binders, and they were coated onto the pre-treated surfaces of specimens. Friction and wear characteristics were evaluated with Falex pin & vee-block test and LFW-1 block-on-ring test. For the corrosion resistant characteristics of the films, salt solution spray corrosion tests were performed. Results showed that MoS$_2$ bonded films containing both inorganic and organic corrosion-resistant additives yielded a synergy effect on anti-corrosion resistance. Also, binders having the better water-proof and thermal stability showed the lower friction and higher corrosion resistance.

• Journal of the Korean Ceramic Society
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• v.49 no.1
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• pp.72-77
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• 2012

In the preparation of a hydroxyapatite [HAp]/gelatin [GEL] nanocomposite, the GEL matrix in aqueous solution of $H_3PO_4$ was modified by the introduction of aspartic acid [Asp], asparagine [Asn], and glycine [Gly]. The addition of Asp, Asn and Gly greatly affected the slurry formation of HAp/GEL nanocomposite and the resulting dry body showed variations in toughness with the addition of the different amino acids. The introduction of Asn into HAp/GEL nanocomposite was effective for producing the organic-inorganic interaction between HAp and GEL, and caused the increase of toughness. The formation reaction of the modified HAP/GEL nanocomposites was investigated by using XRD and FT-IR. The organic-organic interaction between the GEL matrix and the additives of Asp, Asn and Gly was confirmed from FT-IR analysis, and the organic-inorganic interaction between HAp nanocrystallites and the modified GEL matrix was also discussed, using FT-IR spectra patterns. Nanocrystallites of HAp were covalently bound with the GEL macromolecules and differently influenced by the modification species of Asp, Asn, and Gly.

• Prospectives of Industrial Chemistry
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• v.23 no.5
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• pp.21-32
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• 2020

유기전자소자는 용액공정을 통한 대량생산이 가능하기 때문에 기존 무기전자소자에 비해 제조비용이 저렴하고 대면적 생산이 가능하며, 유기분자의 본연 특징으로 인해 유연하고 가벼운 소자를 구현할 수 있다. 그러나 무기 반도체에 비하여 현저히 낮은 전하이동도 특성은 유기전자소자의 상용화에 걸림돌이 되고 있다. 따라서 공액고분자의 결정화도, 모폴로지, 분자배향 최적화를 통한 자기조립 박막 제조는 전하이동을 원활히 하기 때문에 유기전자소자의 개발에 필수적이다. 본 기고에서는 유기전자소자의 활성층으로 사용되는 공액고분자의 자기조립을 유도하기 위한 다양한 특성을 갖는 용매 첨가제의 효과에 대해서 알아보고, 특히 첨가제의 용해도 계수가 공액고분자의 자기조립 거동에 미치는 영향에 대해 자세히 논의하고자 한다.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.769-776
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• 2003

Organic acids, nucleotides and their related compounds (NRCs) of kimchi prepared with salted-fermented fish products (SFFPs) and their alternatives were analyzed at each optimal fermentation (pH $4.2{\pm}0.2$, acidity $0.6{\sim}0.8%$) during fermentation at 20, 10 and $4^{\circ}C$, respectively. The pH and acidity levels of kimchi sharply decreased and increased, respectively until each optimal fermentation period. The levels of organic acids and NRCs in SFFP kimchi were affected by fermentation temperature and the type of additive. Compared with the control, organic acid levels were slightly higher in kimchi with alternative additives, as were NRC rates in kimchi with hydrolysates of oyster and Alaska pollack. Moreover, slightly higher levels of NRC were observed in kimchi with alternative additives than in kimchi with SFFPs. Consequently, these results show that fermentation temperature and the type of additive (SFFPs and their alternatives) affect not only fermentation, but the levels of organic acids and NRCs in kimchi.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.723-733
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• 2016

Intensive researches have been focused on the 3-dimensional packaging technology using through silicon via (TSV) to overcome the limitation in Cu interconnection scaling. Void-free filling of TSV by the Cu electrodeposition is required for the fabrication of reliable electronic devices. It is generally known that sufficient inhibition on the top and the sidewall of TSV, accompanying the selective Cu deposition on the bottom, enables the void-free bottom-up filling. Organic additives contained in the electrolyte locally determine the deposition rate of Cu inside the TSV. Investigation on the additive chemistry is essential for understanding the filling mechanisms of TSV based on the effects of additives in the Cu electrodeposition process. In this review, we introduce various filling mechanisms suggested by analyzing the additives effect, research on the three-additive system containing new levelers synthesized to increase efficiency of the filling process, and methods to improve the filling performance by modifying the functional groups of the additives or deposition mode.

• Journal of Animal Science and Technology
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• v.65 no.5
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• pp.895-911
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• 2023

Processed meat products play a vital role in our daily dietary intake due to their rich protein content and the inherent convenience they offer. However, they often contain synthetic additives and ingredients that may pose health risks when taken excessively. This review explores strategies to improve meat product quality, focusing on three key approaches: substituting synthetic additives, reducing the ingredients potentially harmful when overconsumed like salt and animal fat, and boosting nutritional value. To replace synthetic additives, natural sources like celery and beet powders, as well as atmospheric cold plasma treatment, have been considered. However, for phosphates, the use of organic alternatives is limited due to the low phosphate content in natural substances. Thus, dietary fiber has been used to replicate phosphate functions by enhancing water retention and emulsion stability in meat products. Reducing the excessive salt and animal fat has garnered attention. Plant polysaccharides interact with water, fat, and proteins, improving gel formation and water retention, and enabling the development of low-salt and low-fat products. Replacing saturated fats with vegetable oils is also an option, but it requires techniques like Pickering emulsion or encapsulation to maintain product quality. These strategies aim to reduce or replace synthetic additives and ingredients that can potentially harm health. Dietary fiber offers numerous health benefits, including gut health improvement, calorie reduction, and blood glucose and lipid level regulation. Natural plant extracts not only enhance oxidative stability but also reduce potential carcinogens as antioxidants. Controlling protein and lipid bioavailability is also considered, especially for specific consumer groups like infants, the elderly, and individuals engaged in physical training with dietary management. Future research should explore the full potential of dietary fiber, encompassing synthetic additive substitution, salt and animal fat reduction, and nutritional enhancement. Additionally, optimal sources and dosages of polysaccharides should be determined, considering their distinct properties in interactions with water, proteins, and fats. This holistic approach holds promise for improving meat product quality with minimal processing.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.65-74
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• 1998

To enhance the washing efficiency of soil polluted by hydrophobic organic compounds, the effects of electrolytes and monomeric organic additives on micelle formation and washing efficiency of mixed surfactant solutions were investigated in this study. The surface tensions and critical micelle concentrations(CMCs) of the single and mixed surfactant solutions[$POE_5$/SDS] supplemented by NaCl were measured to investigate the effects on washing efficiency, and the composition ratios of surfactants and NaCl were optimized for the efficient soil washing system. As the mixing ratio of $POE_5$/SDS was increased to 80%, the mixed surfactant with 0.01M NaCl showed more proportional increase of washing efficiency than the mixed surfactant without any salts. The 3% solution of $POE_5$ and SDS(80%/2o%) with 0.01M NaCl showed the washing efficiency of 90%. However, the washing efficiency was not enhanced by NaCl addition to the single surfactant solution of $POE_5$. The CMC of SDS(0.049%) was higher than that of $POE_5$(0.016%), but the CMCs of mixed surfactants were decreased as the mixing ratio of $POE_5$ was increased. Alcohols having longer chain and branched carbon chain were found to be desirable for the soil washing additives.