• Journal of the Korean Institute of Gas
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• v.16 no.2
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• pp.38-44
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• 2012

In recent years, the need for more fuel-efficient and lower-emission vehicles has driven the technical development of alternative fuels such as LPi (Liquid phase LPG injection) which uses pump for the high pressure supply of liquid LPG fuel and is able to meet the limits of better emission levels while it has an advantage of higher power. Although it has the advantage of power and lower emission levels, the characteristics of LPG, such as high vapor pressure, lower viscosity and surface tension than gasoline fuels makes it difficult design system. Therefore most fuel pumps and injectors are imported. In the present study, in order to domestically develop LPG injector which guarantees flow rates and optimal operation, the experimental investigation on leakage and flow rate characteristics of developed prototype injector was carried out at the bench test rig for developed injector.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.846-849
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• 2008

This study employed high performance liquid chromatography (HPLC) coupled to an on-line $ABTS^+$ radical scavenging detection (RSD) system along with HPLC-electro spin impact/mass spectrometry (ESI/MS), to rapidly determine and identify antioxidant compounds occurring in blueberry extract. The extract was separated by HPLC, and then the radical scavenging activities of the separated compounds were evaluated by the on-line coupled $ABTS^+$-RSD system. The negative peaks of the $ABTS^+$-RSD system, which indicates the presence of antioxidant activity, were monitored by measuring the decrease in absorbance at 734 nm. The active components in the blueberry extract were identified by HPLC-ESI/MS using their MS spectra and retention times. According to the data acquired from the on-line HPLC-$ABTS^+$-based assay and HPLC-ESI/MS systems, the antioxidant compounds detected in the blueberry extract were identified as chlorogenic acid and 11 anthocyanins.

• Korean Journal of Pharmacognosy
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• v.50 no.3
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• pp.155-158
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• 2019

Cornus alba (CA) geographically distributes in Korea, Japan, Northeast China and Russia. The cornus species have been used traditionally as anti-inflammatory, hemostatic and diuretic in Korea. Previously, it was reported CA and its separated components have excellent antioxidant, anti-inflammatory and anti-prostate cancer efficacy. Present work, the validation and content determination was tried on the ellagitannin, cornusiin B which were isolated from the CA by using high-performance liquid chromatography (HPLC). As a result, the content of cornusiin B were 3.07% in ethanolic extract of CA.

• Applied Microscopy
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• v.42 no.3
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• pp.174-178
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• 2012

In the present study, the oxidation behavior of $Cu_{50}Zr_{50}$ and $Cu_{46}Zr_{46}Al_8$ metallic glasses has been investigated using transmission electron microscopy with a particular attention on the oxidation behavior in the supercooled liquid state. Identification of the oxidation product after continuous heating treatment shows that in $Cu_{50}Zr_{50}$ metallic glass, $ZrO_2$ with the monoclinic structure forms on the supercooled liquid as well as on the crystallized matrix. On the contrary, in $Cu_{46}Zr_{46}Al_8$ metallic glass, $ZrO_2$ with the tetragonal structure forms on the supercooled liquid, but that with the monoclinic structure forms on the crystallized matrix. The result indicates that the $Cu_{50}Zr_{50}$ metallic glass exhibits far better oxidation resistance in the supercooled liquid state than the $Cu_{46}Zr_{46}Al_8$ metallic glass.

• Analytical Science and Technology
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• v.15 no.3
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• pp.190-195
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• 2002

We analysed mutation of ${\beta}_2$-adrenergic receptor gene that controls bronchial asthma by denaturing high performance liquid chromatography (DHPLC) according to ion-pair reversed-phase high performance liquid chromatography (IP-RP-HPLC). We extracted genomic DNA from 50 asthma patients, amplified DNA using PCR, and analysed PCR product by DHPLC. As a result, we obtained that mutation frequency was 15 (30%) among 50 cases. Consequently DHPLC mutation detection was confirmed that the result of direct sequencing was coincide exactly.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.865-875
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• 2018

Selection of optimum reaction conditions during deoxygenation process of palm oil is essential factor to obtain the maximum yield of bio-jet fuel. In this context, the deoxygenation of palm oil was carried out in a fixed bed reactor with an internal diameter of 1 inch loaded with a 1 wt.% $Pt/Al_2O_3$ catalyst. The composition of the organic liquid product(OLP), which can be utilized as a transportation fuel through the upgrading process, was analyzed by a gas chromatography method. The palm oil/hydrogen ratio and hydrogen pressure in the feed affected the decarboxylation(DCB) and hydrodeoxygenation(HDO) reactions, resulting in a change in the composition of the OLP. As the reaction temperature increased, the continuous cracking reaction of the deoxygenation product was promoted and the product composition in the $C_5{\sim}C_{14}$ region was increased. Thus, the results can help to understand the characteristics of deoxidation reaction of palm oil as well as the subsequent process, hydro-upgrading, to obtain the maximum yield of bio-jet fuel.

• Journal of Ginseng Research
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• v.28 no.1
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• pp.45-51
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• 2004

This study was conducted to investigate the effect of crude saponin of red ginseng and aqueous extracts from several medicinal herbs on the activity of alcohol dehydrogenase(ADH) and aldehyde dehydrogenase(ALDH) in alcohol metabolism. In order to develop a liquid phase product a model product was prepared using functional plants. In case of red ginseng crude saponin, and some medicinal herbs(Puerariae radix, the flower of Puerariae lobata, the fruits of Hovenia dulcis Thunb., Morus alba L.) the relative activity of ADH was significantly increased, which was from 104～114%. The relative activity of ALDH was also significantly increased in the cases of the fruits of Hovenia duicis Thunb., Morus alba L. which was from 102∼106%. To improve of soju flavours by addition of liquid phase product, it is prepared three samples added a given content (0.28%) of chik, ssanghwa and kyungokgo flavour. The total acceptability test showed significant differences among three samples, and it is observed that the sample added ssanghwa flavour get the best grade. As the second acceptability test, the preference of ssanghwa flavoured sample, sample without flavour and a similar product in market was compared. There was no significant difference among three samples.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.451-454
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• 2009

Production and application of biodiesel are expected to grow steadily in the coming years and thus output of its by-product, crude glycerin, will accordingly increase as well. In the present study, gasification of biodiesel by-product as a renewable energy was performed in an entrained flow gasifier to investigate the gasification performance with the operating conditions. Crude glycerin shows a high heating value of 6,000 kcal/kg and low ash and sulphur content. Gasification was conducted in a temperature range of $950\;{\sim}\;1500\;^{\circ}C$. The variation of syngas composition with excess air ratio of 0.17 ~ 0.7 for air or oxygen as a gasification agent was investigated. From the results, syngas heating value, carbon conversion and cold gas efficiency of more than $2500\;kcal/Nm^3$, 95% and 65% were achieved, respectively. The temperature dependency of syngas composition, carbon conversion, and cold gas efficiency shows a similar tendency to excess air ratio at the temperature corresponding to the excess air ratio. The $H_2/CO$ ratio of the product gas was varied from 1.25 to 0.7 with the excess air ratio and this gas composition was favorable for DME synthesis. The optimum excess air ratio for gasification of biodiesel by-product was evaluated to be an approximately 0.35 to 0.4. The present results indicate that crude glycerin can be utilized as a feedstock for gasification to make syngas.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.180-188
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• 2000

Fine multi-hole sheet metal product(FMSMP) is a specific metal plate which is used in color TV and computer monitor. Processes of manufacturing FMSMP are generally composed of coating cleaning exposure and etching processes. After a thin metal plate is made by rolling photosensitive liquid is coated on the metal plate in coating process. Then the coated thin metal plate consecutively passes through exposure process in which upper and lower glasses are compressed by vacuuming the space between glasses and metal plate. In this lowered glasses are compressed by vacuuming the space between glasses and metal plate. In this lowered vacuum state certain part of metal plate is desirably exposed to light and will be etched into forming lots of well-arranged holes with a specific diameter, nowadays to manufacture FMSMP of 17 inch braun tube 80 second is required for complete vacuum but 35 second is applied to manufacture FMSMP in reality. In the present study vacuuming time is tried to reduce for improvement of productivity by analyzing vacuum system and proposing several solutions, for faster vacuuming speed degree of vacuum state between glasses and metal plate is improved by the proposed method and experiments using the proposed method are performed for verification. In addition microstructure of FMSMP is investigated to prevent stain phenomena and to improve quality of the product.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.375-380
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• 1984

A pot experiment was conducted to learn the effect of non-compounded and compounded (with super phosphate) liquid fertilizers made of amino acid fermentation by product and the time of their application on the emergences and yield of orchard grass. Results obtained as follows; 1. The Application of the liquid fertilizers, on seeding day of the orchard grass raised soil pH and salt concentration more than the application on the days before seeding and decreased the number of sprouts of the grass which also lead to a lower yield of the grass compared with the latter. 2. Liquid compound fertilizer, however, tended to reduce the harmful effect on sprouting orchard grass compared with non-compounded liquid fetilizer, particulary in soil of on-lime applied. 3. The application of liquid and liquid compound fetilizers on somewhat acidic bare land a quite ahead of seeding or transplanting crops may not only reduce the effect of the fertilizers, provided the land is free from washing by rain or irrigation water, but also provide better conditions for sprouting and early growth of plant seedings than the use at the pre-seeding or pro-transplanting time.