• Analytical Science and Technology
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• v.14 no.5
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• pp.392-399
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• 2001

The analysis of n-butylbenzene and 1,2-dibromo-3-chloropropane (DBCP) as volatile organic compounds in biota samples was performed by gas chromatography/mass spectrometry-selected ion monitoring mode. The target compounds, n-butylbenzene and DBCP, in biota samples were extracted by headspace solid phase microextraction (SPME) with $100{\mu}m$ polydimethyl siloxane (PDMS) fiber and purge & trap method. The extraction recoveries of these compounds obtained by SPME was 85.8% for n-butylbenzene and 92.4% for DBCP, respectively. Each value of method detection limit were $0.15{\mu}g/kg$ and $0.05{\mu}g/kg$, respectively. While in the case of purge & trap method, the extraction recovery was 115.2% for n-butylbenzene, 80.9% for DBCP and method detection limit were $0.04{\mu}g/kg$ and $0.70{\mu}g/kg$, respectively. The extraction yields and detection limits of these compounds obtained by purge & trap were equivalent to those by SPME.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.2
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• pp.98-106
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• 2005

Population dynamics in the vermicomposting bed was investigated. And harvesting efficiencies of earthworm attracting traps with different attractants, mesh sizes of net and covering materials was evaluated. Peak density of earthworm population was $5kg/m^2$ and therafter its desity kept $4.4{\sim}5.0kg/m^2$. It was evaluated that suitable mesh size of the net was 7mm and proper covering materials of the earthworm attracting trap was cotton quilt. The earthworm harvesting efficiency of trap with attractant was much higher than that of trap without attractant. With more amount of attractant in the trap and with longer setting period of trap onto the vermicomposting bed, the earthworm attracting trap harvested more earthworms. Crushed pear-peel attracted much more earthworms than paper mill sludge, but it was difficult to supply enough amount of crushed pear-peel for practical need. Sugar solution(10%) with tab water was proven to be an alternative to crushed pear-peel because its attracting effect on earthworm was as high as crushed pear-peel and it was easy to prepare and supply in large quantity.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.168-177
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• 2021

The effects of the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture on the activities of osteoblast differentiation and the restraint of osteoclast formation were investigated. the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture in the human osteoblast "MG-63" cell, was examined in relation to alkaline phosphatase (ALP) activity and alizarin red stains. In order to observe the effects of osteoclasts formation, we analyzed RAW 264.7 cell tartrate-resistant acid phosphatase (TRAP) activity and TRAP stains. In cytotoxicity testing, it was confirmed that apple extract is safe at a concentration of 50 ㎍/㎖ or less. The ALP activity and Bone calcification formation ability were the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture had a lower activity than that of control group. However the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture significantly reduced activity of TRAP in the RAW 264.7 osteoclastic cell generation and effectively Inhibited the TRAP(+) multinuclear cells. Thus, our results demonstrate that the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture enhances the inhibitory activity of bone-resorption in RAW 264.7 cells. In conclusion, the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture seem to be effective in the prevention and treatment of bone related disorders.

• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.335-340
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• 2022

After detection of red imported fire ant (Solenopsis invicta) at Gamman port in Busan in September of 2017, Animal and Plant Quarantine Agency has surveilled invasive ants in the area with a high invasion risk of ants. However, existing surveillance traps have several limitations such as captured ants could escape easily or it is very hard to set up the trap on a hard ground like concrete or asphalt. To solve these problems, we developed a new trap using multiple narrow tubes to attract ants to the inside of the trap and make it hard for ants to escape. The new trap can be easily set up under various conditions. The new trap has more than four times ant capturing efficacy compared to conventional pitfall traps. Our results confirmed that the new trap could prevent captured ants from escaping. We hope that this newly developed trap would contribute to the prevention of invasive ants.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.6
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• pp.60-66
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• 1992

This study describes a theoretical analysis for the wall temperature of ceramic filter trap and pressures of inlet and outlet channel in the filter trap. In this study, the maximum wall temperature through filter trap length with time during the regeneration period showed a tendency moving from forward to backward. The pressure change of filter trap increased at the initial combustion but decreased with the combustion to be activated. So the pressure difference between initial and end regeneration at the inlet channel showed about 2kPa. The thermal regeneration period of this filter trap in the theoretical analysis showed about 200seconds in which the wall temperature was similar to the case of initial condition and the pressure showed about 1 kPa.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.155-159
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• 2002

This paper describes the development process of mosquito trap with the effect of air cleaning by using the substance-field analysis and evolution pattern of systems in the theory of inventive problem solving (TRIZ). We g(It the concept of the mosquito trap with mosquito attractants instead of mosquito reluctants such as mosquito stick coil and skin medicine with bad and toxic smell. The number of mosquitos traped by one trap near cattle shed per one night in summer, was over 10 thousands with some effects of air cleaning

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.191-191
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• 1999

A Purge & Trap Concentrator was used to analyze various volatile organic compounds(VOCs) in wat-er. The object of this study was to observe the purge efficiency of 40 VOCs in water according to the change of parameters (purge time drypurge time sample temperature) and to determine the optimum condition for VOCs using the purge & Trap concentrator interfaced with a narrow capillary connected to a gas chromatography/mass spectrometry. The optimum condition of purge and trap is as follows: purge time at 11min drypurge time at 5min sample temperature at 6$0^{\circ}C$ at constant purge flow (40mol/min) constant desorption flow(20ml/min) desorption temperature(2$25^{\circ}C$) and desorption time (1min) At this analytical condition the detection limits of VOCs was in the range of 0.1~0.5$\mu$g/ml and the purge efficiency of each compound was over 70%.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.892-897
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• 2007

This paper presents the output filter design and the output characteristic analysis by cut-off frequency set up of the LCR filter on NPC multi-level inverter with trap-filter. The single-phase NPC three-level inverter operates at low switching frequency. The proposed LC trap filter is comprised of a conventional LCR output filter, by using LC trap filter the need for high damping resistor and low LC cut-off frequency is eliminated. Also. low damping resistor is increased the output filter system. The multilevel inverter system used NPC type inverter in proper system for high power application and controller is used DSP(TMS320C31). The effectiveness of proposed system confirmed the validity through SPICE simulation and experimental results.

• Journal of Environmental Health Sciences
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• v.20 no.4
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• pp.53-59
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• 1994

Since trihalomethanes (THMs) and other volatile organic compounds (VOCs) were detected and measured in drinking water supplies in 1974, because of the frequent occurrence of these compounds and the potential health hazard they pose, several methods for detecting VOCs have been developed. The most widely accepted method for the analysis of THMs and other VOCs is a purgeand-trap method. In the analysis of VOCs by purge-and-trap,there are several factors which may give rise to errors. Some of the factors to be considered are purge time, carryover effect, cryofocusing temperature, and trap desorption temperature. In this study,many aspects of purge-and-trap were investigated. Understanding the sources of error makes it possible to adapt the analysis parameters to compensate for such effects.

• BMB Reports
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• v.45 no.1
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• pp.1-6
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• 2012

Hsp90 is one of the most conserved molecular chaperones ubiquitously expressed in normal cells and over-expressed in cancer cells. A pool of Hsp90 was found in cancer mitochondria and the expression of the mitochondrial Hsp90 homolog, TRAP1, was also elevated in many cancers. The mitochondrial pool of chaperones plays important roles in regulating mitochondrial integrity, protecting against oxidative stress, and inhibiting cell death. Pharmacological inactivation of the chaperones induced mitochondrial dysfunction and concomitant cell death selectively in cancer cells, suggesting they can be target proteins for the development of cancer therapeutics. Several drug candidates targeting TRAP1 and Hsp90 in the mitochondria have been developed and have shown strong cytotoxic activity in many cancers, but not in normal cells in vitro and in vivo. In this review, recent developments in the study of mitochondrial chaperones and the mitochondria-targeted chaperone inhibitors are discussed.