• Natural Product Sciences
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• v.14 no.2
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• pp.113-117
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• 2008

Saururus chinensis is a commonly used folk herb for the treatment of edema and liver diseases in Korea. To study the biological activity of Saururus chinensis in bone metabolism, we evaluated the effect of its extracts on osteoclast differentiation in vitro using primary mouse bone marrow-derived macrophages. Methanol extract (ME) from dried roots of Saururus chinensis was partitioned into methylene chloride (MF), ethyl acetate (EF), n-butanol (BF) and water fractions (WF). Tartrate-resistance acid phosphatase (TRAP) activity assay and western blot analysis were performed to determine the effect on osteoclast differentiation and mitogen-activated protein (MAP) kinases activation. ME, MF and EF dramatically inhibited receptor activator of ${NF-kB}$ ligand (RANKL)-induced formation of multinucleated osteoclasts and activation of MAP kinases. This study firstly demonstrated that ME, MF and EF of Saururus chinensis have the potential to inhibit the osteoclast differentiation, which results from the inhibition of MAP kinases activations in part.

• Korean Membrane Journal
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• v.7 no.1
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• pp.58-66
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• 2005

Nanofiltration (NF) of a dyeing wastewater was carried out using polyamide NF-membranes. Before applying the wastewater to the membrane process, it was pretreated with various chemical coagulants such as alum, ferric chloride and HOC-100A. In order to see the effect of the pretreatment of the wastewater using chemical coagulants on the membrane separation process, the optimum conditions for the coagulation and sedimentation process using the chemical coagulants were sought. By the pretreatment, despite the different coagulants used, the chemical oxygen demand (COD) and UV-absorbance of the wastewater were lowered by more than $70\%$. The pretreated wastewater was then applied to the membrane process. The effect of the coagulants used for the pretreatment on the membrane fouling was studied. From this study, it was found that the HOC-100A was the best out of the coagulants used far the removal of the materials that could cause membrane fouling.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.7-14
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• 2015

In this study, land farming and chemical oxidation of a diesel-contaminated site is compared to evaluate the environmental impact during soil remediation using the Spreadsheet for Environmental Footprint Analysis by U.S. EPA. Each remediation process is divided into four phases, consisting of soil excavation, backfill and transportation (Phase 0), construction of remediation facility (Phase 1), remediation operation (Phase 2), and restoration of site and waste disposal (Phase 3). Environmental footprints, such as material use, energy consumption, air emission, water use and waste generation, are analyzed to find the way to minimize the environmental impact. In material use and waste generation, land farming has more environmental effect than chemical oxidation due to the concrete and backfill material used to construct land farming facility in Phase 1. Also, in energy use, land farming use about six times more energy than chemical oxidation because of cement production and fuel use of heavy machinery, such as backhoe and truck. However, carbon dioxide, commonly considered as important factor of environmental impact due to global warming effect, is emitted more in chemical oxidation because of hydrogen peroxide production. Water use of chemical oxidation is also 2.1 times higher than land farming.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.215-220
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• 2012

ZnO nanoparticles were synthesized through a facile route and were used as ozonation catalysts. With the increase of calcination temperature ($150-300^{\circ}C$), surface hydroxyl groups and catalytic efficiency of asobtained ZnO decreased remarkably, and the ZnO obtained at $150^{\circ}C$ showed the best catalytic activity. Compared with ozonation alone, the degradation efficiency of phenol increased above 50% due to the catalysis of ZnO-150. In the reaction temperatures range from $5^{\circ}C$ to $35^{\circ}C$, ZnO nanocatalyst revealed remarkable catalytic properties, and the catalytic effect of ZnO was better at lower temperature. Through the effect of tertbutanol on degradation of phenol and the catalytic properties of ZnO on degradation of nitrobenzene, it was proposed that the degradation of phenol was ascribed to the direct oxidation by ozone molecules based on solidliquid interface reaction.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1435-1440
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• 2013

To investigate the influence of the carbon matrix on the electrochemical performance of Si/C composites, four types of Si/C composites were prepared using graphite, petroleum coke, pitch and sucrose as carbon precursors. A ball mill was used to prepare Si/C blends from graphite and petroleum coke, whereas a dispersion technique was used to fabricate Si/C composites where Si was embedded in disordered carbon matrix derived from pitch or sucrose. The Si/pitch-based carbon composite showed superior Si utilization (96% in the first cycle) and excellent cycle retention (70% after 40 cycles), which was attributed to the effective encapsulation of Si and the buffering effect of the surrounding carbon matrix on the silicon particles.

• Polymer(Korea)
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• v.31 no.2
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• pp.105-110
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• 2007

We investigated resin, thinner, painting, and injection for analyzing the chemical effect of polymer, and made the optimum solution with the best performance of ABS (acrylonitrile butadiene styrene) resin. The effect depended on chemical material especially its chemical and physical properties instead of mechanical transformation. When we looked over ABS resin, injection, chemical material and painting, we found out thinner was the main factor for painting problem. Throughout this test, we could solve the problem, secure the system for control process and drop many factors for changing quality.

• Journal of the Korean Society of Combustion
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• v.3 no.1
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• pp.11-19
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• 1998

The influence of oxidant addition on soot formation is investigated experimentally with ethylene, propane and mixture fuel co-flow diffusion flames. Oxidant addition into fuel shows the increase of integrated soot volume fractions for ethylene, ethylene/ethane and ethylene/methane mixture flames. However, the increase of integrated soot volume fraction with oxidant addition was not significant for propane and ethylene/propane mixture flames. This discrepancy is explained with $C_2\;and\;C_3$ chemistry at the early stage of soot formation process. The oxidant addition increases the concentration of $C_3H_3$ in the soot formation region, and therefore, enhances soot formation process. A new soot formation rate model that includes both dilution effect and chemical effect of oxygen is suggested to interpret the increase of integrated soot volume fractions with oxidant addition into ethylene. Also, the role of adiabatic flame temperature for the chemical effect of oxygen addition into fuel was reviewed. The influence of oxidant or diluent addition into fuel on soot formation process are the fuel dilution effect, the adiabatic flame temperature altering effect and/or the chemical effect of oxygen. Their relative importance could change with fuel structure and adiabatic flame temperature.

• Applied Chemistry for Engineering
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• v.21 no.6
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• pp.670-675
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• 2010

Inorganic-organic hybrid material such as vinyl-nano sized silica ball was synthesized by acrylo-alkoxysilane and nano silica ball with different particle size. And then they were formulated into acrylic-melamine clearcoat. This material is fully characterized with various analytical methods and applied for strength measurement. The glossy effect, matting effect and anti-scratching properties of materials were investigated for further growth and maintenance. When the particle size of nano silica ball is 20~30 nm, the glossy retain effect was increased by 7% compared to bare acrylic-melamine clearcoat. When a commercially available silica Aerosil 200 (Hydrophilic fumed silica, average particle size 12 nm, Degussa) react with vinyl alkoxysilane vinyl-fumed silica complex form. The vinyl-fumed silica along with clearcoat increases only 2% increase at glossy retain. Nano-scratch test results also support the glossy retain effect of vinyl nano-sized silica ball in clearcoat.

• YAKHAK HOEJI
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• v.33 no.3
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• pp.167-174
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• 1989

KR-1008 and KR-30006 are 1,4-dihydropyridine derivatives, new vasodilatory calcium antagonists from KRICT. Calcium antagonistic properties of the compounds were studied in the isolated heart (Langendorff preparation), pulmonary artery (vasodilation), and in the papillary muscle (negative inotropic effect) of the guinea pig. Antihypertensive effect were also investigated after i.v. or oral administration in the SHR (spontaneously hypertensive rat). They produced a sigificant inhibition of Ca-induced contraction in the guinea pig pulmonary artery at the concentrations of above $10^{-8}M$. The negative inotropic effect of the electrically stimulated papillary muscle appeared from the concentration of $10^{-6}M$, which is about hundred times higer than the concentration of vasodilation effect. Left ventricular pressure also decreased from the concentration of $3\;{\times}\;10^{-6}M$ in KR-1008 and KR-3006 in the Langendorff heart preparations. Coronary flow rate increased from $10^{-6}M$ in KR-1008 and nicardipine and appeared no change in KR-30006. The antihypertensive effect of KR-1008 (EC 20: $2.9\;{\mu}g/kg$) was potent more than nicardipine (EC 20: $3.4\;{\mu}g/kg$) and than Kr-30006 (EC 20: $6.8\;{\mu}g/kg$) was, after i.v. bolus injection in the anesthetized SHR. The antihypertensive effect in the conscious SHR appeared 30 minutes after oral administration of 10 mg/kg and persisted 4 hrs in KR-1008 and 12 hrs in KR-30006. Heart rate tended to increase for 0.5-1 hr after oral administration of the test compounds.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.348-353
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• 2005

The extracts from natural and fermented products such as Artemisia plants, Rhodiola Salientness, fermented soybeans and soybean paste were used to investigate the whitening effect. 10 g of Artemisia plant were added to 300 mL of ethanol and extracted by sonification at room temperature for 3 h. The extract was further partitioned by the equal volume percent in the order of the n-hexane, chloroform and ethyl acetate. 5 g of Rhodiola salientness was also added to 150 mL of methanol and extracted at the room temperature for 12 h. The effluents from a chromatographic column ($3.9{\times}250mm$, $C_{18}$, $15{\mu}m$) were collected and concentrated in two parts. The extraction of fermented soybeans and soybean paste were done by 60% ethanol. In this work, tyrosinase inhibitory activity and melanin inhibitory effect were measured to confirm the whitening effect. The water layer of Artemisia princeps Pampan showed the good inhibitory of antioxidant, while the hexane layer of Artemisia iwayomogi Kitamura and the chloroform layer of Artemisia princeps Pampan had the excellent melanin inhibitory effect. The Rhodiola salientness had the superior whitening effect to the arbutin in in-vivo melanin production ratio assay. However, the fermented soybeans and soybean paste did not show any whitening effect.