• International Journal of Concrete Structures and Materials
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• v.10 no.3
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• pp.383-391
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• 2016

This paper reports the results of an experimental program involving several small-scale columns which were constructed to simulate corrosion damage in the field using two accelerated corrosion techniques namely, constant voltage and constant current. A total of six columns were cast for this experiment. For one pair of regular RC columns, corrosion was accelerated using constant voltage and for another pair, corrosion was accelerated using constant current. The remaining pair of regular RC columns was used as control. In the experiment, all the columns were subjected to cyclic wetting and drying using sodium chloride (NaCl) solution. The currents were monitored on an hourly interval and cracks were visually checked throughout the test program. After the specimens had suffered sufficient percentage steel loss, all the columns including the control were tested to failure in compression. The test results generated show that accelerated corrosion using impressed constant current produces more corrosion damage than that using constant voltage. The results suggest that the constant current approach can be better used to simulate corrosion damage of reinforced concrete structures and to assess the effectiveness of various materials, repair strategies and admixtures to resist corrosion damage.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.805-816
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• 2014

We investigated the quality characteristics and resulting sensory evaluation of semi-dried silver pomfret treated with high hydrostatic pressure (HHP) processing and brining for 14 days at 4 and $10^{\circ}C$ to evaluate the effects of treatment with HHP processing. HHP treatment and brining could cause compaction of fibers and the space between muscle. The G' values of all samples were higher than the G" values and the tan ${\delta}$ values of the tissue ranged from 0.222 to 0.251 with no further changes observed during storage. HHP treatment and brining significantly increased the total color difference, and the HHP and brine-treated group scored significantly higher than the others in terms of sensory evaluation. HHP treatment combined with brining could have a significant effect on the quality characteristics of the semi-dried products and their storage stability, and it is suggested from the results that they may have the potential to satisfy the requirements to produce commercially marketable food grade products.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.8
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• pp.78-85
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• 1995

We fabricated the Pb$_{1-0.28{\alpha}}La_{0.28}TiO_{3}$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of 100% perovskite phase by drying at 350$^{\circ}C$ after each coating and final annealing at 650$^{\circ}C$. Its electrical properties were measured from the planar capacitors fabricated on the Pt/Ti/SiO$_{2}$/Si substrate. By the P-E hysteresis measurement, its paraelectric phase was identified and its dielectric constant and leakage current density were measured as 936 and 1.1${\mu}A/cm^{2}$, respectively. Those electrical values indicate that the PLT(28) thin film is the most successful candidate for the capacitor dielectrics of ULSI DRAMs at the present.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3343-3352
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• 2014

Chemoprevention is an attempt to use nontoxic natural and synthetic substances or their mixtures to intervene the relatively early stages of carcinogenesis, before invasive characteristics are manifested. The consumption of fruits is well known to reduce the risk of human cancers. Although most fruits are available only on a seasonal basis, recent advances in food processing technologies have made it possible to extend the shelf life of fruits and fruit-products. Fruits can be preserved by applying different drying processes to reduce the moisture content. Different varieties of dried fruits are now sold in supermarkets, thereby making them readily accessible to consumers. Since oxidative stress and chronic inflammation play important roles in cancer development, dried fruits with antioxidative and anti-inflammatory properties hold promise for cancer chemoprevention. The antioxidant, anti-inflammatory and chemopreventive activities of dried fruits are largely attributed to their polyphenols and vitamins. Dried fruits contain adequate amounts of bioactive principles, such as anthocyanins, acetogenins, catechins, coumarins, phenolic acids, terpenes, xanthones, and others. Since numerous health beneficial phytochemicals in fruits are conserved even after processing, regular intake of dried fruits can help prevent cancer. This review addresses the chemopreventive potential of representative dried fruits and their active constituents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.299-306
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• 2001

As a part of basic investigation for utilization of canned food processing by-products, a food components of the canned oyster processing waste water such as boiled and released water(BRW), wash water(WW) were investigated and compared with hot-water extracts from oyster. From the results of measuring heavy metal conte수, viable cells and coliform group, the canned oyster processing waste waters might not invoke health risk in using food resource. The contents of taste compounds (free amino acids, ATP related compounds, TMA (O) and total creatinine) of BRW and WW accounted for about 254% and 95%, respectively, in comparison with those of control (hot-water extract from oyster). The BRW showed a very high content of salt in comparing to the WW and control. In descending order, the values of whiteness index was WW, control and BRW. Sensory scores for color, oyster flavor intensity and saline taste were not significantly different between WW and control. But, BRW had the highest score in oyster flavor intensity, while had the lowest score in color and saline taste. But, the color and saline taste of BRW might be able to control by some pretreatment (concentration and drying in mild condition, desalination and recipe control etc). These results indicated that BRW and WW generated from various step during canned oyster processing could be a potential food resource by controlling of saline taste and color intensity.

• Journal of Powder Materials
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• v.18 no.3
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• pp.250-255
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• 2011

The potential application of ultrafine cerium oxide (ceria, $CeO_2$) as an oxygen gas sensor has been investigated. Ceria was synthesized by a thermochemical process: first, a precursor powder was prepared by spray drying cerium-nitrate solution. Heat treatment in air was then performed to evaporate the volatile components in the precursor, thereby forming nanostructured $CeO_2$ having a size of approximately 20 nm and specific surface area of 100 $m^2/g$. After sintering with loosely compacted samples, hydrogen-reduction heat treatment was performed at 773K to increase the degree of non-stoichiometry, x, in $CeO_{2-x}$. In this manner, the electrical conductivity and oxygen-response ability could be enhanced by increasing the number of oxygen vacancies. After the hydrogen reduction at 773K, $CeO_{1.5}$ was obtained with nearly the same initial crystalline size and surface. The response time $t_{90}$ measured at room temperature was extremely short at 4 s as compared to 14 s for normally sintered $CeO_2$. We believe that this hydrogen-reduced ceria can perform capably as a high-performance oxygen sensor with good response abilities even at room temperature.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.103-107
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• 2007

Elsholtzia spp., a herbaceous perennial plant grown worldwide, have been used as a folklore medicine. Due to the presence of flavonoid in their extracts, Elsholtzia spp. have various functional properties. The objective of this research was to compare the amount of flavonoids in Elsholtzia spp. extracts in order to improve the potential of by using their functional properties. Elsholtzia spp. were collected in various areas of Korea. These were divided into leaf, flower, stem, and root. Each sample was dried using various drying method and ground to a powder. The powdered sample prepared was extracted with 80% ethanol. Extracts were analysed for the content of total flavonoids and apigenin by HPLC. Higher content of flavonoids was observed in the extracts of leaves and flowers. In previous study, apigenin among flavonoids was detected from Elsholtzia spp. so, apigenin content was analysed by HPLC. According to the results, the extracts of leaf and flower had the higher apigenin content than other samples.

• Journal of Pharmaceutical Investigation
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• v.28 no.4
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• pp.257-266
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• 1998

To improve the solubility and dissolution rate of acyclovir (ACV), which is low oral bioavailability due to its properties of slight solubility in water and incomplete gastrointestinal absorption, the solid inclusion complexes of ACV with ${\alpha}CD$, ${\beta}CD$, $DM{\beta}CD$ in molar ratio of 1:1 were prepared by the freeze-drying method. The inclusion complexes were investigated by solubility study, UV, IR and DSC. The dissolution rate of ACV was significantly increased by ACV-CDs inclusion complex formation in artificial intestinal fluid at pH 6.8. The enhanced dissolution rate of ACV could be due to an increase of solubility and the formation of an amorphous structures through inclusion complexation with CDs. Especially, $ACV-DM{\beta}CD$ inclusion complex enhanced the maximum plasma concentration levels and AUC following oral administration compared to those of ACV alone. The present results suggest that $ACV-DM{\beta}CD$ inclusion complex serves as a potential carrier for improving the solubility, the dissolution rate and the bioavailability of ACV.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1404-1410
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• 2009

Chestnut flours (CFs) were produced from 3 chestnut samples (Aydin, Kutahya, and Bursa) by 2 different methods (boiled and oven-dried: BOD-CF and freeze-dried: FD-CF). Functional properties and effects of CF addition (10, 20, and 30%) on the qualities of regular and low-fat cookie were investigated. The freeze drying significantly increased water solubility of CFs but decreased their water binding capacity. The emulsion capacity and stability of FD-CFs were higher than those of BOD-CFs. At pH 4, 6, 8, and 10 FD-CFs had better gelation properties. Spread ratio (SR) values of BOD-CF supplemented regular or low-fat cookies decreased with increasing CF levels. Hardness values of CF supplemented regular cookies were generally lower compared to control. SR and hardness values of FD-CF supplemented cookies were higher than those of BOD-CF supplemented ones. Surface colors of the cookies were darker with FD-CF addition as compared to BODCF addition. In low-fat cookies, the sample supplemented with 10% Kutahya FD-CF had the highest taste-flavor value. FDCF supplementation generally resulted in higher appearance and taste-flavor scores than BOD-CF supplementation in cookies.

• Carbon letters
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• v.27
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• pp.18-25
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• 2018

In this study, graphene oxide(GO) was used as drug carriers to amorphize poorly watersoluble drugs via a co-spray drying process. Two poorly water-soluble drugs, fenofibrate and ibuprofen, were investigated. It was found that the drug molecules could be in the graphene nanosheets in amorphous or nano crystalline forms and thus have a significantly enhanced dissolution rate compared with the counterpart crystalline form. In addition, the dissolution of the amorphous drug enwrapped with the graphene oxide was higher than that of the amorphous drug in activated carbon (AC) even though the AC possessed a larger specific surface area than that of the graphene oxide. The amorphous formulations also remained stable under accelerated storage conditions ($40^{\circ}C$ and 75% relative humidity) for a study period of 14 months. Therefore, graphene oxide could be a potential drug carrier and amorphization agent for poorly water-soluble drugs to enhance their bioavailability.