• Bulletin of the Korean Chemical Society
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• v.22 no.10
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• pp.1145-1148
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• 2001

• Environmental Engineering Research
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• v.21 no.1
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• pp.52-57
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• 2016

Sediment is a useful natural source but deteriorated continually by anthropogenic and industrial sources. Therefore, it is imperative to search a suitable method for improving or restoring sediment quality. Sediment has been tested to identify the effects of some external agents on a polluted area for 28 days. Chemical analysis and total viable counts (TVC) test have been conducted for 4 days interval to assess their performance. The analyses of chemical oxygen demand (COD), acid volatile sulfide (AVS), total phosphorous (T-P), total nitrogen (T-N) indicate that the chemical agents was more efficient to improve sediment quality whereas the microbial agent was more efficient for nutrient releasing from sediment. Oxygen releasing property of the chemical agent was thought to be providing with more congenial environment for the higher growth of the bacterial community than the direct application of microbial agents.

• Macromolecular Research
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• v.15 no.7
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• pp.617-622
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• 2007

A simple and economic antistatic agent, (2-methacryloyloxyethyl)acid phosphate (acryl phosphate), was synthesized via the reaction of 2-hydroxyethyl methacrylate with phosphorus pentoxide. The acryl phosphate antistatic agent, synthesized in this study, was introduced into poly(methyl methacrylate) (PMMA) resin via copolymerization with MMA. This antistatic agent provides the PMMA matrix with excellent antistatic properties, including surface resistance and electric charge. A comparison of the present antistatic agent with other commercial agents demonstrated the excellence of not only its electrical, but also its thermal and mechanical properties.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.411-414
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• 2019

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.328-331
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• 1995

A successful, computer-aided design support system can help a process designer focus on making effective design decisions, not merely tedious routine calculations. Such a system is essential to enhance quality of design in terms of economics, environmental benignity, reliability, robustness, and operability. Such a statement is even more accepted when applied to conceptual design problems, where gross design specifications are given while a combinatorial number of design alternatives exists. This paper presents an agent-based approach as a systematic and efficient way to design a design support system for the synthesis of conceptual chemical processes. An agent-based approach allows us to handle design knowledge as an object and thus greatly improve the modularity and reusability of that knowledge. Such modularity and reusability lead to the increased productivity in the development of a design support system and the increased ease in the relaxation of design decisions and the generation of design alternatives, both of which functions are critically important in dealing with the complexity and uncertainty of conceptual design problems.

• Journal of Powder Materials
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• v.13 no.4 s.57
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• pp.278-284
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• 2006

Spherical Ag powder was prepared in the system of $AgNO_3\;and\;NaBH_4$ by wet chemical reduction method. The size of Ag powder was increased as the reaction temperature and the concentration of reducing agent was decreased in the constant concentration of dispersion agent. Optimum conditions of producing Ag powder having $1.39{\mu}m$ of D50 was 1M of $AgNO_3$, 0.5M of $NaBH_4$, 1.5g of Gelatine in the room temperature.

• Macromolecular Research
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• v.10 no.2
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• pp.127-134
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• 2002

Microporous polypropylene hollow fiber membrane was fabricated from isotactic polypropylene-soybean oil system by melt spinning process. Addition of nucleating agent accelerated the crystallization rate and elevated the crystallization temperature. Nucleating agent increased the number of nuclei and spherulites, which offered more inter-spherulitic amorphous sites for stretching. Benzoic acid, adipic acid, and dibenzylidene sorbitol were selected as nucleating agents, and their characteristics and effects were investigated by thermal and optical analyses. Spherulite growth and micropore formation characteristics were correlated with the kind of nucleating agent. Benzoic acid and adipic acid showed the remarkable nucleating effect, while dibenzylidene sorbitol was less effective than those. Nucleating agents also helped the sample have uniform microporous structure. Increase of nucleating agent composition enhanced the nucleation effect to some extent. Nucleating agents played very important roles in enhancing the membrane porosity and water flux.

• Journal of Environmental Science International
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• v.14 no.10
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• pp.973-978
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• 2005

Biodegradable oil gelling agent was prepared, and their oil absorption capacities using light oil, lubricant oil and corn oil were investigated. The result showed that the oil absorption capacity was depended on the amount of surfactant and starch added, and was increased in the order of light oil, lubricant oil and corn oil. Also, the oil-absorption capacity was saturated within 30 min at $18^{\circ}C$. The biodegradability of the prepared biodegradable oil gelling agent was also studied by determination of reduced sugar produced after enzymatic hydrolysis. Their surface morphologies and thermal properties of the prepared biodegradable oil gelling agent were observed by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.339-342
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• 2003

This study is intended to investigate the influence of chemical admixture on bleeding of concrete. According to the results, the amount of bleeding with elapse of time does not make much difference in the case of naphthalene type water reducing agent(RN), Naphthalene type high performance water reducing agent(HN) and Melamine type high performance water reducing agent(HM), but it is largest in the case of Polycarbonic acid type high performance water reducing agent(HP). Bleeding speed also is highest in the case of HP in comparison with other chemical admixture. This prove that high performance water reducing agent like HP has little effect on fluidity of concrete, but influences the amount of bleeding more greatly, instead. As properties of hardened concrete, compressive strength makes no difference in the case of RN, HN and HM, but on the other hand, it increases in the case of HP due to a decrease of air content and the large amount of bleeding.

• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.20-26
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• 2005

For developing digital printing textiles, special pretreatment processes are necessary. These processes include developing formulation of coating agent and coating processes. The pretreatment were investigated with the variation concentration of anti-migration agent, fixation chemical etc.. The printing qualities according to pretreatment conditions were studied with color yield, printed capital letter sharpness and washing fastness. It was observed that the concentration of anti-migration agent, fixation agent(alkali) was closely related to printing qualities. For developing industrial technology of cellulosic digital printing textiles, optimum viscosity of pretreatment coating formulation is very important factor.